Solutions | Chemistry | Visionlearning

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It also examines how concentration affects freezing point, boiling point, and vapor pressure."> <meta name="keywords" content="solubility, solutions, solutes, aqueous, colligative, properties, dissolve"> <meta name="viewport" content="width=device-width, initial-scale=1.0, shrink-to-fit=no"> <meta name="msvalidate.01" content="D8E20F39AD48052260032E56DE409970"> <script type="application/ld+json"> { "@context": "http://schema.org/", "@type": "Article", "mainEntityOfPage": { "@type": "WebPage", "@id": "https://visionlearning.com/en/library/chemistry/1/solutions/266" }, "name": "Solutions", "headline": "Solutions: Molarity, solubility, and colligative properties", "author": [ { "@type": "Person", "name": "Robin Marks, M.A." } , { "@type": "Person", "name": "Anthony Carpi, Ph.D." }], "datePublished": "2017-10-15 19:31:23", "dateModified": "2017-02-12T08:30:00+05:00", "image": { "@type": "ImageObject", "url": "/img/library/moduleImages/featured_image_266-23061209064829.jpeg", "width": 696, "height": 464 }, "publisher": { "@type": "Organization", "name": "Visionlearning, Inc.", "logo": { "@type": "ImageObject", "url": "http://visionlearning.com/images/logo.png", "width": 278, "height": 60 } }, "description": "Aqueous solutions are found throughout our world, and their chemistry depends in part on how much of a dissolved substance is in them. This module explores how substances dissolve, why some substances don’t dissolve, and how we express the concentration of a solution. The module describes the forces that hold particles together and interactions that keep dissolved particles apart. It also examines how concentration affects freezing point, boiling point, and vapor pressure.", "keywords": "solubility, solutions, solutes, aqueous, colligative, properties, dissolve", "inLanguage": { "@type": "Language", "name": "English", "alternateName": "en" }, "copyrightHolder": { "@type": "Organization", "name": "Visionlearning, Inc." }, "copyrightYear": "2017"} </script> <meta property="og:url" content="https://visionlearning.com/en/library/chemistry/1/solutions/266"> <meta property="og:title" content="Solutions | Chemistry | Visionlearning" /> <meta property="og:type" content="website"> <meta property="og:site_name" content="Visionlearning"> <meta property="og:description" content="Aqueous solutions are found throughout our world, and their chemistry depends in part on how much of a dissolved substance is in them. This module explores how substances dissolve, why some substances don’t dissolve, and how we express the concentration of a solution. The module describes the forces that hold particles together and interactions that keep dissolved particles apart. It also examines how concentration affects freezing point, boiling point, and vapor pressure."> <meta property="og:image" content="https://visionlearning.com/images/logo.png"> <meta property="fb:admins" content="100000299664514"> <link rel="stylesheet" type="text/css" href="/css/visionlearning.css">  <link rel="stylesheet" type="text/css" href="/css/visionlearning-icons.css">  <link rel="preconnect" as="font" href="https://fonts.gstatic.com" crossorigin> <link href="https://fonts.googleapis.com/css2?family=Open+Sans:ital,wght@0,400;0,700;1,400;1,700&family=Schoolbell&display=swap" rel="stylesheet"> <style> textarea.myEditor { width: 90%; height: 350px; } </style> <script type="text/x-mathjax-config" src="/js/mathjax-config.js"></script> <script id="MathJax-script" async src="/js/mathjax/tex-svg.js"></script> <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-9561344156007092" crossorigin="anonymous"></script> </head> <body>  <header 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<li><a href="/en/library/earth-science/6/factors-that-control-earths-temperature/234">Factors that Control Earth's Temperature</a></li> <li><a href="/en/library/earth-science/6/circulation-in-the-atmosphere/255">Circulation in the Atmosphere</a></li> </ul> </div> <button class="accordion__button" id="acc-button-hazards" data-accordion="button" aria-controls="acc-panel-hazards" aria-expanded="false"> <span class="accordion__button__label"> Hazards </span> </button> <div class="accordion__panel" id="acc-panel-hazards" data-accordion="panel" aria-labelledby="acc-button-hazards" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/earth-science/6/natural-hazards-and-risk/288">Natural Hazards and Risk</a></li> </ul> </div> <button class="accordion__button" id="acc-button-earth-history" data-accordion="button" aria-controls="acc-panel-earth-history" aria-expanded="false"> <span class="accordion__button__label"> Earth History </span> </button> <div class="accordion__panel" 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aria-controls="acc-panel-ecology" aria-expanded="false"> <span class="accordion__button__label"> Ecology </span> </button> <div class="accordion__panel" id="acc-panel-ecology" data-accordion="panel" aria-labelledby="acc-button-ecology" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/environmental-science/61/biodiversity-i/276">Biodiversity I</a></li> <li><a href="/en/library/environmental-science/61/biodiversity-ii/281">Biodiversity II</a></li> <li><a href="/en/library/environmental-science/61/ecosystem-services/279">Ecosystem Services</a></li> <li><a href="/en/library/environmental-science/61/population-biology/287">Population Biology</a></li> </ul> </div> <button class="accordion__button" id="acc-button-earth-cycles" data-accordion="button" aria-controls="acc-panel-earth-cycles" aria-expanded="false"> <span class="accordion__button__label"> Earth Cycles </span> </button> <div class="accordion__panel" id="acc-panel-earth-cycles" data-accordion="panel" aria-labelledby="acc-button-earth-cycles" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/environmental-science/61/the-nitrogen-cycle/98">The Nitrogen Cycle</a></li> <li><a href="/en/library/environmental-science/61/the-carbon-cycle/95">The Carbon Cycle</a></li> <li><a href="/en/library/environmental-science/61/the-phosphorus-cycle/197">The Phosphorus Cycle</a></li> </ul> </div> <button class="accordion__button" id="acc-button-scientific-research" data-accordion="button" aria-controls="acc-panel-scientific-research" aria-expanded="false"> <span class="accordion__button__label"> Scientific Research </span> </button> <div class="accordion__panel" id="acc-panel-scientific-research" data-accordion="panel" aria-labelledby="acc-button-scientific-research" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/environmental-science/61/collaborative-research-in-the-arctic-towards-understanding-climate-change/183">Collaborative Research in the Arctic Towards Understanding Climate Change</a></li> <li><a href="/en/library/environmental-science/61/atmospheric-chemistry-research-that-changed-global-policy/211">Atmospheric Chemistry Research that Changed Global Policy</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-general-science" data-accordion="button" aria-controls="acc-panel-general-science" aria-expanded="false"> <span class="accordion__button__label"> General Science </span> </button> <div class="accordion__panel" id="acc-panel-general-science" data-accordion="panel" aria-labelledby="acc-button-general-science" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-methods" data-accordion="button" aria-controls="acc-panel-methods" aria-expanded="false"> <span class="accordion__button__label"> Methods </span> </button> <div class="accordion__panel" id="acc-panel-methods" data-accordion="panel" aria-labelledby="acc-button-methods" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/general-science/3/the-scientific-method/45">The Scientific Method</a></li> </ul> </div> <button class="accordion__button" id="acc-button-measurement" data-accordion="button" aria-controls="acc-panel-measurement" aria-expanded="false"> <span class="accordion__button__label"> Measurement </span> </button> <div class="accordion__panel" id="acc-panel-measurement" data-accordion="panel" aria-labelledby="acc-button-measurement" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/general-science/3/the-metric-system/47">The Metric System</a></li> </ul> </div> <button class="accordion__button" id="acc-button-physical-properties" data-accordion="button" aria-controls="acc-panel-physical-properties" aria-expanded="false"> <span class="accordion__button__label"> Physical Properties </span> </button> <div class="accordion__panel" id="acc-panel-physical-properties" data-accordion="panel" aria-labelledby="acc-button-physical-properties" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/general-science/3/temperature/48">Temperature</a></li> <li><a href="/en/library/general-science/3/density-and-buoyancy/37">Density and Buoyancy</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-math-in-science" data-accordion="button" aria-controls="acc-panel-math-in-science" aria-expanded="false"> <span class="accordion__button__label"> Math in Science </span> </button> <div class="accordion__panel" id="acc-panel-math-in-science" data-accordion="panel" aria-labelledby="acc-button-math-in-science" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-equations" data-accordion="button" aria-controls="acc-panel-equations" aria-expanded="false"> <span class="accordion__button__label"> Equations </span> </button> <div class="accordion__panel" id="acc-panel-equations" data-accordion="panel" aria-labelledby="acc-button-equations" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/math-in-science/62/unit-conversion/144">Unit Conversion</a></li> <li><a href="/en/library/math-in-science/62/linear-equations/194">Linear Equations</a></li> <li><a href="/en/library/math-in-science/62/exponential-equations-i/206">Exponential Equations I</a></li> <li><a href="/en/library/math-in-science/62/exponential-equations-ii/210">Exponential Equations II</a></li> <li><a href="/en/library/math-in-science/62/scientific-notation/250">Scientific Notation</a></li> <li><a href="/en/library/math-in-science/62/measurement/257">Measurement</a></li> </ul> </div> <button class="accordion__button" id="acc-button-statistics" data-accordion="button" aria-controls="acc-panel-statistics" aria-expanded="false"> <span class="accordion__button__label"> Statistics </span> </button> <div class="accordion__panel" id="acc-panel-statistics" data-accordion="panel" aria-labelledby="acc-button-statistics" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/math-in-science/62/introduction-to-descriptive-statistics/218">Introduction to Descriptive Statistics</a></li> <li><a href="/en/library/math-in-science/62/introduction-to-inferential-statistics/224">Introduction to Inferential Statistics</a></li> <li><a href="/en/library/math-in-science/62/statistical-techniques/239">Statistical Techniques</a></li> </ul> </div> <button class="accordion__button" id="acc-button-trigonometric-functions" data-accordion="button" aria-controls="acc-panel-trigonometric-functions" aria-expanded="false"> <span class="accordion__button__label"> Trigonometric Functions </span> </button> <div class="accordion__panel" id="acc-panel-trigonometric-functions" data-accordion="panel" aria-labelledby="acc-button-trigonometric-functions" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/math-in-science/62/wave-mathematics/131">Wave Mathematics</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-physics" data-accordion="button" aria-controls="acc-panel-physics" aria-expanded="false"> <span class="accordion__button__label"> Physics </span> </button> <div class="accordion__panel" id="acc-panel-physics" data-accordion="panel" aria-labelledby="acc-button-physics" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-light-and-optics" data-accordion="button" aria-controls="acc-panel-light-and-optics" aria-expanded="false"> <span class="accordion__button__label"> Light and Optics </span> </button> <div class="accordion__panel" id="acc-panel-light-and-optics" data-accordion="panel" aria-labelledby="acc-button-light-and-optics" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/physics/24/the-nature-of-light/132">The Nature of Light</a></li> <li><a href="/en/library/physics/24/electromagnetism-and-light/138">Electromagnetism and Light</a></li> </ul> </div> <button class="accordion__button" id="acc-button-mechanics" data-accordion="button" aria-controls="acc-panel-mechanics" aria-expanded="false"> <span class="accordion__button__label"> Mechanics </span> </button> <div class="accordion__panel" id="acc-panel-mechanics" data-accordion="panel" aria-labelledby="acc-button-mechanics" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/physics/24/defining-energy/199">Defining Energy</a></li> <li><a href="/en/library/physics/24/waves-and-wave-motion/102">Waves and Wave Motion</a></li> <li><a href="/en/library/physics/24/gravity/118">Gravity</a></li> <li><a href="/en/library/physics/24/thermodynamics-i/200">Thermodynamics I</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-process-of-science" data-accordion="button" aria-controls="acc-panel-process-of-science" aria-expanded="false"> <span class="accordion__button__label"> Process of Science </span> </button> <div class="accordion__panel" id="acc-panel-process-of-science" data-accordion="panel" aria-labelledby="acc-button-process-of-science" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-introduction" data-accordion="button" aria-controls="acc-panel-introduction" aria-expanded="false"> <span class="accordion__button__label"> Introduction </span> </button> <div class="accordion__panel" id="acc-panel-introduction" data-accordion="panel" aria-labelledby="acc-button-introduction" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/the-process-of-science/176">The Process of Science</a></li> </ul> </div> <button class="accordion__button" id="acc-button-the-culture-of-science" data-accordion="button" aria-controls="acc-panel-the-culture-of-science" aria-expanded="false"> <span class="accordion__button__label"> The Culture of Science </span> </button> <div class="accordion__panel" id="acc-panel-the-culture-of-science" data-accordion="panel" aria-labelledby="acc-button-the-culture-of-science" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/the-nature-of-scientific-knowledge/185">The Nature of Scientific Knowledge</a></li> <li><a href="/en/library/process-of-science/49/scientists-and-the-scientific-community/172">Scientists and the Scientific Community</a></li> <li><a href="/en/library/process-of-science/49/scientific-ethics/161">Scientific Ethics</a></li> <li><a href="/en/library/process-of-science/49/scientific-institutions-and-societies/162">Scientific Institutions and Societies</a></li> </ul> </div> <button class="accordion__button" id="acc-button-ideas-in-science" data-accordion="button" aria-controls="acc-panel-ideas-in-science" aria-expanded="false"> <span class="accordion__button__label"> Ideas in Science </span> </button> <div class="accordion__panel" id="acc-panel-ideas-in-science" data-accordion="panel" aria-labelledby="acc-button-ideas-in-science" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/theories-hypotheses-and-laws/177">Theories, Hypotheses, and Laws</a></li> <li><a href="/en/library/process-of-science/49/scientific-controversy/181">Scientific Controversy</a></li> <li><a href="/en/library/process-of-science/49/creativity-in-science/182">Creativity in Science</a></li> </ul> </div> <button class="accordion__button" id="acc-button-research-methods" data-accordion="button" aria-controls="acc-panel-research-methods" aria-expanded="false"> <span class="accordion__button__label"> Research Methods </span> </button> <div class="accordion__panel" id="acc-panel-research-methods" data-accordion="panel" aria-labelledby="acc-button-research-methods" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/the-practice-of-science/148">The Practice of Science</a></li> <li><a href="/en/library/process-of-science/49/experimentation-in-scientific-research/150">Experimentation in Scientific Research</a></li> <li><a href="/en/library/process-of-science/49/description-in-scientific-research/151">Description in Scientific Research</a></li> <li><a href="/en/library/process-of-science/49/comparison-in-scientific-research/152">Comparison in Scientific Research</a></li> <li><a href="/en/library/process-of-science/49/modeling-in-scientific-research/153">Modeling in Scientific Research</a></li> </ul> </div> <button class="accordion__button" id="acc-button-data" data-accordion="button" aria-controls="acc-panel-data" aria-expanded="false"> <span class="accordion__button__label"> Data </span> </button> <div class="accordion__panel" id="acc-panel-data" data-accordion="panel" aria-labelledby="acc-button-data" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/data-analysis-and-interpretation/154">Data Analysis and Interpretation</a></li> <li><a href="/en/library/process-of-science/49/uncertainty-error-and-confidence/157">Uncertainty, Error, and Confidence</a></li> <li><a href="/en/library/process-of-science/49/statistics-in-science/155">Statistics in Science</a></li> <li><a href="/en/library/process-of-science/49/using-graphs-and-visual-data-in-science/156">Using Graphs and Visual Data in Science</a></li> </ul> </div> <button class="accordion__button" id="acc-button-scientific-communication" data-accordion="button" aria-controls="acc-panel-scientific-communication" aria-expanded="false"> <span class="accordion__button__label"> Scientific Communication </span> </button> <div class="accordion__panel" id="acc-panel-scientific-communication" data-accordion="panel" aria-labelledby="acc-button-scientific-communication" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/process-of-science/49/understanding-scientific-journals-and-articles/158">Understanding Scientific Journals and Articles</a></li> <li><a href="/en/library/process-of-science/49/utilizing-the-scientific-literature/173">Utilizing the Scientific Literature</a></li> <li><a href="/en/library/process-of-science/49/peer-review-in-scientific-publishing/159">Peer Review in Scientific Publishing</a></li> <li><a href="/en/library/process-of-science/49/the-how-and-why-of-scientific-meetings/186">The How and Why of Scientific Meetings</a></li> </ul> </div> </div> </div> <button class="accordion__button" id="acc-button-scientists-and-research" data-accordion="button" aria-controls="acc-panel-scientists-and-research" aria-expanded="false"> <span class="accordion__button__label"> Scientists and Research </span> </button> <div class="accordion__panel" id="acc-panel-scientists-and-research" data-accordion="panel" aria-labelledby="acc-button-scientists-and-research" role="region"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-button-scientific-research" data-accordion="button" aria-controls="acc-panel-scientific-research" aria-expanded="false"> <span class="accordion__button__label"> Scientific Research </span> </button> <div class="accordion__panel" id="acc-panel-scientific-research" data-accordion="panel" aria-labelledby="acc-button-scientific-research" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/scientists-and-research/58/collaborative-research-in-the-arctic-towards-understanding-climate-change/183">Collaborative Research in the Arctic Towards Understanding Climate Change</a></li> <li><a href="/en/library/scientists-and-research/58/from-stable-chromosomes-to-jumping-genes/184">From Stable Chromosomes to Jumping Genes</a></li> <li><a href="/en/library/scientists-and-research/58/an-elegant-experiment-to-test-the-process-of-dna-replication/187">An Elegant Experiment to Test the Process of DNA Replication</a></li> <li><a href="/en/library/scientists-and-research/58/the-founding-of-neuroscience/233">The Founding of Neuroscience</a></li> <li><a href="/en/library/scientists-and-research/58/tracking-endangered-jaguars-across-the-border/189">Tracking Endangered Jaguars across the Border</a></li> <li><a href="/en/library/scientists-and-research/58/atmospheric-chemistry-research-that-changed-global-policy/211">Atmospheric Chemistry Research that Changed Global Policy</a></li> <li><a href="/en/library/scientists-and-research/58/revolutionizing-medicine-with-monoclonal-antibodies/220">Revolutionizing Medicine with Monoclonal Antibodies</a></li> <li><a href="/en/library/scientists-and-research/58/uncovering-the-mysteries-of-chronic-mountain-sickness/238">Uncovering the Mysteries of Chronic Mountain Sickness</a></li> </ul> </div> <button class="accordion__button" id="acc-button-profiles-in-science" data-accordion="button" aria-controls="acc-panel-profiles-in-science" aria-expanded="false"> <span class="accordion__button__label"> Profiles in Science </span> </button> <div class="accordion__panel" id="acc-panel-profiles-in-science" data-accordion="panel" aria-labelledby="acc-button-profiles-in-science" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/scientists-and-research/58/luis-e.-miramontes/232">Luis E. Miramontes</a></li> <li><a href="/en/library/scientists-and-research/58/bernardo-houssay/237">Bernardo Houssay</a></li> <li><a href="/en/library/scientists-and-research/58/craig-lee/256">Craig Lee</a></li> <li><a href="/en/library/scientists-and-research/58/david-ho/241">David Ho</a></li> <li><a href="/en/library/scientists-and-research/58/louis-tompkins-wright/244">Louis Tompkins Wright</a></li> <li><a href="/en/library/scientists-and-research/58/carlos-j.-finlay/217">Carlos J. Finlay</a></li> <li><a href="/en/library/scientists-and-research/58/cecilia-payne/290">Cecilia Payne</a></li> <li><a href="/en/library/scientists-and-research/58/jazmin-scarlett/291">Jazmin Scarlett</a></li> <li><a href="/en/library/scientists-and-research/58/ramari-stewart/292">Ramari Stewart</a></li> <li><a href="/en/library/scientists-and-research/58/johnson-cerda/300">Johnson Cerda</a></li> <li><a href="/en/library/scientists-and-research/58/ellen-ochoa/201">Ellen Ochoa</a></li> <li><a href="/en/library/scientists-and-research/58/ruth-benerito/205">Ruth Benerito</a></li> <li><a href="/en/library/scientists-and-research/58/franklin-chang-díaz/219">Franklin Chang Díaz</a></li> <li><a href="/en/library/scientists-and-research/58/percy-lavon-julian/221">Percy Lavon Julian</a></li> <li><a href="/en/library/scientists-and-research/58/luis-walter-alvarez/229">Luis Walter Alvarez</a></li> <li><a href="/en/library/scientists-and-research/58/france-anne-dominic-córdova/230">France Anne-Dominic Córdova</a></li> </ul> </div> </div> </div> </div> </div> </li> <li>  <button class="button" data-toggle="dropdown">Chemistry </button> <div class="nav__dropdown box-shadow-1 padding-1"> <div class="accordion accordion--secondary font-size-sm"> <div class="accordion accordion--secondary"> <button class="accordion__button" id="acc-sub-button-atomic-theory-and-structure" data-accordion="button" aria-controls="acc-sub-panel-atomic-theory-and-structure" aria-expanded="false"> <span class="accordion__button__label"> Atomic Theory and Structure </span> </button> <div class="accordion__panel" id="acc-sub-panel-atomic-theory-and-structure" data-accordion="panel" aria-labelledby="acc-sub-button-atomic-theory-and-structure" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/chemistry/1/early-ideas-about-matter/49">Early Ideas about Matter</a></li> <li><a href="/en/library/chemistry/1/the-periodic-table-of-elements-i/52">The Periodic Table of Elements I</a></li> <li><a href="/en/library/chemistry/1/the-periodic-table-of-elements-ii/296">The Periodic Table of Elements II</a></li> <li><a href="/en/library/chemistry/1/the-periodic-table-of-elements-iii/297">The Periodic Table of Elements III</a></li> <li><a href="/en/library/chemistry/1/the-periodic-table-of-elements-iv/298">The Periodic Table of Elements IV</a></li> <li><a href="/en/library/chemistry/1/the-periodic-table-of-elements-v/299">The Periodic Table of Elements V</a></li> <li><a href="/en/library/chemistry/1/atomic-theory-i/50">Atomic Theory I</a></li> <li><a href="/en/library/chemistry/1/atomic-theory-ii/51">Atomic Theory II</a></li> <li><a href="/en/library/chemistry/1/atomic-theory-iii/223">Atomic Theory III</a></li> <li><a href="/en/library/chemistry/1/atomic-theory-iv/231">Atomic Theory IV</a></li> <li><a href="/en/library/chemistry/1/the-mole-and-atomic-mass/53">The Mole and Atomic Mass</a></li> </ul> </div> <button class="accordion__button" id="acc-sub-button-physical-states-and-properties" data-accordion="button" aria-controls="acc-sub-panel-physical-states-and-properties" aria-expanded="false"> <span class="accordion__button__label"> Physical States and Properties </span> </button> <div class="accordion__panel" id="acc-sub-panel-physical-states-and-properties" data-accordion="panel" aria-labelledby="acc-sub-button-physical-states-and-properties" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/chemistry/1/states-of-matter/120">States of Matter</a></li> <li><a href="/en/library/chemistry/1/substances/280">Substances</a></li> <li><a href="/en/library/chemistry/1/properties-of-solids/209">Properties of Solids</a></li> <li><a href="/en/library/chemistry/1/properties-of-liquids/222">Properties of Liquids</a></li> <li><a href="/en/library/chemistry/1/properties-of-gases/245">Properties of Gases</a></li> <li><a href="/en/library/chemistry/1/diffusion-i/216">Diffusion I</a></li> <li><a href="/en/library/chemistry/1/kinetic-molecular-theory/251">Kinetic-Molecular Theory</a></li> <li class="current">Solutions</li> <li><a href="/en/library/chemistry/1/water/267">Water</a></li> </ul> </div> <button class="accordion__button" id="acc-sub-button-chemical-relationships" data-accordion="button" aria-controls="acc-sub-panel-chemical-relationships" aria-expanded="false"> <span class="accordion__button__label"> Chemical Relationships </span> </button> <div class="accordion__panel" id="acc-sub-panel-chemical-relationships" data-accordion="panel" aria-labelledby="acc-sub-button-chemical-relationships" role="region"> <ul class="nav text-color-link"> <li><a href="/en/library/chemistry/1/chemical-bonding/55">Chemical Bonding</a></li> <li><a href="/en/library/chemistry/1/stoichiometry/270">Stoichiometry</a></li> <li><a href="/en/library/chemistry/1/chemical-equations/268">Chemical Equations</a></li> <li><a href="/en/library/chemistry/1/acids-and-bases-i/271">Acids and Bases I</a></li> 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id="skip-header-content"> <div class="margin-bottom-5"> <div class="container narrow wide--lg margin-y-4"> <article class="module"> <header class="module__header"> <span class="subcategory"> <strong><em>Physical States and Properties</em></strong> </span> <h1>Solutions: <sub><em>Molarity, solubility, and colligative properties</em></sub></h1> <p class="byline">by Robin Marks, M.A., Anthony Carpi, Ph.D.</p> </header> <nav class="module__tabs"> <ul class="tabs-nav tabs-nav--pill tabs-nav--horizontal--md library"> <li> <a href="/en/library/chemistry/1/solutions/266/reading" class="is-active" aria-current="page" >Reading</a> </li> <li> <a href="/en/library/chemistry/1/solutions/266/quiz" >Quiz</a> </li> <li> <a href="/en/library/chemistry/1/solutions/266/resources" >Teach with this</a> </li> </ul> </nav> <hr class="module__divider" />  <div class="module__tools"> <aside class="module__tools__container border-radius box-shadow-1"> <div class="tabs tabs--toggle-mobile--lg" role="tablist"> <ul class="tab__buttons"> <li> <button class="button button--icon-over-text" aria-label="In this module" aria-controls="tab-panel-module__tools" aria-selected="true" role="tab"> <span class="button__icon"> <span class="icon icon-list" aria-hidden="true"></span> </span> <span class="button__text">Contents</span> </button> </li> <li> <button class="button button--icon-over-text" aria-controls="tab-panel-toggle-terms" aria-selected="false" role="tab"> <span class="button__icon"> <span class="icon icon-glossary-highlight"></span> </span> <span class="button__text">Glossary Terms</span> </button> </li> <li> <button class="button button--icon-over-text" aria-controls="tab-panel-toggle-ngss" aria-selected="false" role="tab"> <span class="button__icon"> <span class="icon icon-ngss" aria-hidden="true"></span> </span> <span class="button__text">NGSS</span> </button> </li> </ul> <div class="tabs__panel shown" id="tab-panel-module__tools" aria-labelledby="tab-button-module__tools" role="tabpanel"> <div class="table-of-contents"> <p class="table-of-contents__title"> Table of Contents </p> <ul class="table-of-contents__nav"> <li><a href="/en/library/chemistry/1/solutions/266#toc_1">What does it mean to dissolve?</a> </li> <li><a href="/en/library/chemistry/1/solutions/266#toc_2">Dissolving polar solutes in a polar solvent</a> </li> <li><a href="/en/library/chemistry/1/solutions/266#toc_3">Dissolving ionic solutes in a polar solvent</a> </li> <li><a href="/en/library/chemistry/1/solutions/266#toc_4">Dissolving nonpolar solutes in a nonpolar solvent</a> </li> <li><a href="/en/library/chemistry/1/solutions/266#toc_5">Dissolving involves energy</a> </li> <li><a href="/en/library/chemistry/1/solutions/266#toc_6">Molarity: How much solute is in the solution?</a> </li> <li><a href="/en/library/chemistry/1/solutions/266#toc_7">Solubility: A balance of forces</a> </li> <li><a href="/en/library/chemistry/1/solutions/266#toc_8">Solubility rules</a> </li> <li><a href="/en/library/chemistry/1/solutions/266#toc_9">Colligative properties: concentration matters</a> </li> <li> <ul> <li><a href="/en/library/chemistry/1/solutions/266#toc2_1">Freezing point depression</a> </li> </ul> </li> <li> <ul> <li><a href="/en/library/chemistry/1/solutions/266#toc2_2">Vapor pressure lowering and boiling point elevation</a> </li> </ul> </li> </ul> </div> </div> <div class="tabs__panel" id="tab-panel-toggle-terms" aria-labelledby="tab-button-toggle-terms" role="tabpanel"> <div class="reading-toggle"> <div class="reading-toggle__switch"> <div class="form-entry__option__switch"> <label> <input type="checkbox" name="termsToggleSwitch" id="terms-toggle-switch" /> <span class="switch__slider"></span> <span class="option__label text-decoration-none font-size-md"> Highlight Glossary Terms </span> </label> </div> </div> <div class="reading-toggle__help"> <p> <em> Activate glossary term highlighting to easily identify key terms within the module. Once highlighted, you can click on these terms to view their definitions. </em> </p> </div> </div> <div class="glossary-container"></div> </div> <div class="tabs__panel" id="tab-panel-toggle-ngss" aria-labelledby="tab-button-toggle-ngss" role="tabpanel"> <div class="reading-toggle"> <div class="reading-toggle__switch"> <div class="form-entry__option__switch"> <label> <input type="checkbox" name="ngssToggleSwitch" id="ngss-toggle-switch" /> <span class="switch__slider"></span> <span class="option__label text-decoration-none font-size-md"> Show NGSS Annotations </span> </label> </div> </div> <div class="reading-toggle__help"> <p> <em> Activate NGSS annotations to easily identify NGSS standards within the module. Once highlighted, you can click on them to view these standards. </em> </p> </div> </div> <div class="ngss-container"></div> </div> </div> </aside> <div class="margin-3"> <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-9561344156007092" crossorigin="anonymous"></script>  <ins class="adsbygoogle" style="display:block" data-ad-client="ca-pub-9561344156007092" data-ad-slot="7634263342" data-ad-format="auto" data-full-width-responsive="true"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> </div>     <div class="module__main"> <div class="module__main__container"> <div class="accordion">  <button class="accordion__button" id="acc-button-key-concepts" data-accordion="button" aria-controls="acc-panel-key-concepts" aria-expanded="true" tabindex="0"> Did you know? </button> <div class="accordion__panel shown show" id="acc-panel-key-concepts" data-accordion="panel" aria-labelledby="acc-button-key-concepts" role="region"> <div class="accordion__panel__content"> <p>Did you know that the more concentrated a solution is, the lower its freezing point and the higher its boiling point? This is why antifreeze keeps your car engine from freezing in frigid weather or overheating on very hot days. Forces at work on a molecular level determine what happens when a solution is formed. A look at the chemistry of solutions reveals why some substances dissolve more easily than others and why some compounds don’t dissolve at all.</p> </div> </div>  <button class="accordion__button" id="acc-button-table-of-contents" data-accordion="button" aria-controls="acc-panel-table-of-contents" aria-expanded="false" tabindex="0"> Key concepts </button> <div class="accordion__panel" id="acc-panel-table-of-contents" data-accordion="panel" aria-labelledby="acc-button-table-of-contents" role="region" aria-hidden="true"> <div class="accordion__panel__content"> <ul class="bulleted"> <li><p>A solution is formed when solute particles are randomly distributed and dissolved in a solvent.</p></li> <li><p>Molarity is a measure of the solute concentration in a solution, and remains consistent when a fraction of the solution is poured off.</p></li> <li><p>In polar solutions, the charges on both the solute and solvent particles keep the solute dissolved, as the polar solvent molecules surround the solute particles and keep them apart.</p></li> <li><p>The relative solubility of a salt or polar compound in water is a balance of two forces: the attraction between atoms of the salt molecule, and the attraction between the ions and the water molecules.</p></li> <li><p>Solutions of non-polar solutes in non-polar solvent are driven by London dispersion forces, another type of attraction between molecules.</p></li> <li><p>Colligative properties of solutions—freezing point depression, boiling point elevation, and vapor pressure lowering—are related to the concentration of solute molecules but independent of the specific solute type.</p></li> </ul> </div> </div>  <button class="accordion__button" id="acc-button-terms-you-should-know" data-accordion="button" aria-controls="acc-panel-terms-you-should-know" aria-expanded="false" tabindex="0"> Terms you should know </button> <div class="accordion__panel" id="acc-panel-terms-you-should-know" data-accordion="panel" aria-labelledby="acc-button-terms-you-should-know" role="region" aria-hidden="true"> <div class="accordion__panel__content"> <dl> <dt>dissolve </dt> <dd> process of a solid mixing into a liquid and creating a solution </dd> <dt><a href="/en/glossary/view/polar">polar </a></dt> <dd> carrying an electrical charge </dd> <dt><a href="/en/glossary/view/solubility">solubility </a></dt> <dd> the extent to which a solid dissolves in a particular solvent</dd> </dl> </div> </div> </div> <section> <p>Ancient Romans are still admired today for their ingenious water <mark class="term" data-term="system" data-term-def="A group of interacting, interrelated or interdependent components that form a complex whole. The size of the system is defined for&hellip;" data-term-url="/en/glossary/view/system/3904">system</mark>, engineered with a series of aqueducts and underground lead pipes. The upper classes enjoyed water delivered to their homes, just as we have today. What Romans didn’t realize about their water, however, was that little by little the lead pipes were dissolving into it. And, consequently, the lead was ending up inside the Romans who drank the water. In this module, we’ll look at what actually happens when a <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compound</mark> dissolves, why some things dissolve more easily than others, and how the Romans might have been able to use knowledge of <mark class="term" data-term="solubility" data-term-def="The extent to which a solid dissolves in a particular solvent." data-term-url="/en/glossary/view/solubility/7572">solubility</mark> to remove the lead from their water. </p>  <div class="figure"> <figure> <button class="lightbox-button" data-lightbox-src="/img/library/large_images/image_11750.jpg" data-lightbox="image"> <img src="/img/library/modules/mid266/Image/VLObject-11750-171015011022.jpg" alt="Figure 1: The Roman aqueduct in Segovia, Spain." /> </button> <figcaption> <p><strong>Figure 1</strong>: The Roman aqueduct in Segovia, Spain.</p> <span class="credit">image ©David Corral Gadea</span> </figcaption> </figure> </div> <p>While researchers <mark class="term" data-term="debate" data-term-def="A reasoned discussion of opposing points in an argument." data-term-url="/en/glossary/view/debate/8242">debate</mark> whether Rome’s lead levels were high enough to cause widespread poisoning, one thing is certain: the Romans drinking that water couldn’t see the lead in it. That’s because the lead was dissolved as <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark>, much the same way that the sodium and chloride <mark class="term" data-term="ion" data-term-url="/en/glossary/view/ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;">ions</mark> disappear into water when you stir table <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> into it.</p><p>Still, the Romans’ plumbing (from the Latin word for lead, <em>plumbum</em>, that gives rise to lead’s symbol, Pb) was so clever that the <mark class="term" data-term="system" data-term-def="A group of interacting, interrelated or interdependent components that form a complex whole. The size of the system is defined for&hellip;" data-term-url="/en/glossary/view/system/3904">system</mark> was adopted around the world. In the United States, many homes were built with lead pipes until the 1960s, and lead is present in some form in the plumbing of many modern buildings. In fact, lead is one of the chemicals most home water purifiers are designed to remove from our drinking water.</p> <p><section id="toc_1" class=""> <h2>What does it mean to dissolve?</h2></p> <p>Some Romans questioned the use of lead pipes, noting that people who made the pipes and other lead items seemed to have a pale, unhealthy appearance. But even those concerned that lead was a toxin didn’t have a precise way of measuring how much lead was in their water. Our ability to understand how much of a substance is dissolved into a given amount of water requires knowledge that grew over the centuries.</p> <div class="container margin-y-4 text-align-center"> <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-9561344156007092" crossorigin="anonymous"></script>  <ins class="adsbygoogle" style="display:inline-block;width:300px;height:250px" data-ad-client="ca-pub-9561344156007092" data-ad-slot="9090201191"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> <p>For starters, we need to consider what a <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> actually is. The <a href="/library/module_viewer.php?mid=222">Properties of Liquids</a> module describes a solution as a liquid with another substance dissolved in it. We use the term <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark> for the liquid something is dissolved in, and the dissolved substance the <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark>. A solute can be either <mark class="term" data-term="solid" data-term-def="A collection of atoms or molecules that are held together so that, under constant conditions, they maintain a defined shape and&hellip;" data-term-url="/en/glossary/view/solid/7571">solid</mark>, <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark>, or <mark class="term" data-term="gas" data-term-def="The state of matter characterized by its non-condensed nature and ability to flow. Unlike liquids, molecules within a gas remain far&hellip;" data-term-url="/en/glossary/view/gas/8725">gas</mark>.</p><p>Many things that we drink are <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solutions</mark> containing substances dissolved in them, and sometimes we even mix those solutions ourselves. <mark class="term" data-term="electrolyte" data-term-def="A substance that dissociates into 2 or more oppositely charged ions in water. Electrolytic solutions conduct electricity because the charged&hellip;" data-term-url="/en/glossary/view/electrolyte/1562">Electrolyte</mark> (or “energy”) drink powders, for example, often contain the <mark class="term" data-term="sugar" data-term-def="A water-soluble crystalline carbohydrate. There are many types of sugar of varying degrees of sweetness, including fructose, which occurs naturally in&hellip;" data-term-url="/en/glossary/view/sugar/5309">sugar</mark> called <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> and a variety of <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salts</mark>. Many athletes (and weekend warriors) will use these powders to make <mark class="term" data-term="energy" data-term-def="An abstract property defined as the capacity to do work. The basic forms of energy include chemical, electrical, mechanical, nuclear, and&hellip;" data-term-url="/en/glossary/view/energy/1497">energy</mark> drinks when they are working out. When you add the drink powder to your water, the sugar and salts disappear. Both were <mark class="term" data-term="solid" data-term-def="A collection of atoms or molecules that are held together so that, under constant conditions, they maintain a defined shape and&hellip;" data-term-url="/en/glossary/view/solid/7571">solids</mark>, but they become dissolved in the <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark> water and aren’t visible anymore. The solids have separated into <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> at the molecular level. </p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form name="cc11810"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">A solvent is _____.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-11810-0-option-a" name="quiz-option-11810" type="radio" value="a substance that is dissolved into a liquid" > <span class="option__label"> <span class="screen-reader-only">a.</span> a substance that is dissolved into a liquid </span> </label> <span class="quiz__response" id="response-11810-0"> <strong>Incorrect.</strong> </span> </div> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-11810-1-option-b" name="quiz-option-11810" type="radio" value="the liquid into which a substance is dissolved" > <span class="option__label"> <span class="screen-reader-only">b.</span> the liquid into which a substance is dissolved </span> </label> <span class="quiz__response" id="response-11810-1"> <strong>Correct!</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_2"> <h2>Dissolving polar solutes in a polar solvent</h2><p><mark id="ngss-530" class="ngss">Sugar and <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> dissolve into water in different ways. <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">Glucose</mark>, like all types of <mark class="term" data-term="sugar" data-term-def="A water-soluble crystalline carbohydrate. There are many types of sugar of varying degrees of sweetness, including fructose, which occurs naturally in&hellip;" data-term-url="/en/glossary/view/sugar/5309">sugar</mark>, is a covalently bonded <mark class="term" data-term="polar" data-term-def="Carrying an electrical charge." data-term-url="/en/glossary/view/polar/8730">polar</mark> <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecule</mark>, meaning that some parts of it have a slight positive <mark class="term" data-term="charge" data-term-def="A quantity of electricity." data-term-url="/en/glossary/view/charge/8258">charge</mark> and other parts a slight negative charge. Water is also a <mark class="term" data-term="polar molecule" data-term-def="Refer to polar covalent molecule." data-term-url="/en/glossary/view/polar+molecule/2568">polar molecule</mark>.</mark></p><p><mark id="ngss-531" class="ngss">In <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark> water, areas of opposite <mark class="term" data-term="charge" data-term-def="A quantity of electricity." data-term-url="/en/glossary/view/charge/8258">charge</mark> on nearby water <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> are attracted to each other, creating what are called hydrogen <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark>. <mark class="term" data-term="hydrogen bond" data-term-def="A strong dipole-dipole attraction between two or more molecules, at least one of which has a hydrogen atom bonded to an&hellip;" data-term-url="/en/glossary/view/hydrogen+bond/1560">Hydrogen bonds</mark> are strong attractions between charged <mark class="term" data-term="atom" data-term-def="The smallest unit of an element that retains the chemical properties of the element. Atoms can exist alone or in&hellip;" data-term-url="/en/glossary/view/atom/1509">atoms</mark> on separate molecules. They are strong enough to affect the properties of the liquid and its ability to dissolve certain types of <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solutes</mark>.</mark></p><p>Glucose is a good example. When <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> and water interact, the positive areas of the glucose <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecule</mark> are attracted to the negative areas of the water molecules, forming hydrogen <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark> with the water molecules.</p>  <div class="figure"> <figure> <button class="lightbox-button" data-lightbox-src="/img/library/large_images/image_11752.jpg" data-lightbox="image"> <img src="/img/library/modules/mid266/Image/VLObject-11752-171015041017.jpg" alt="Figure 2: The structure of glucose. (From: Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014." WikiJournal of Medicine, 1(2). DOI:10.15347/wjm/2014.010)" /> </button> <figcaption> <p><strong>Figure 2</strong>: The structure of glucose. (From: Blausen.com staff (2014). "Medical gallery of Blausen Medical 2014." <em>WikiJournal of Medicine, 1</em>(2). DOI:10.15347/wjm/2014.010)</p> <span class="credit">image ©BruceBlaus</span> </figcaption> </figure> </div> <p>Similarly, the negative ends of the <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecule</mark> are attracted to the positive areas of the water molecules. In this way, the interaction allows the water molecules to surround each glucose molecule, separating them from their neighbors and dissolving them. If the <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark> did not overcome the attraction between individual glucose molecules, they would clump together and remain undissolved. This is, in fact, what would happen if you tried to dissolve the drink powder in a non-polar solvent such as olive oil, rather than water.</p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form name="cc11880"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">Hydrogen bonds are formed by strong attractions between _____.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-11880-0-option-a" name="quiz-option-11880" type="radio" value="atoms in different molecules" > <span class="option__label"> <span class="screen-reader-only">a.</span> atoms in different molecules </span> </label> <span class="quiz__response" id="response-11880-0"> <strong>Correct!</strong> </span> </div> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-11880-1-option-b" name="quiz-option-11880" type="radio" value="atoms within a single molecule" > <span class="option__label"> <span class="screen-reader-only">b.</span> atoms within a single molecule </span> </label> <span class="quiz__response" id="response-11880-1"> <strong>Incorrect.</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_3"> <h2>Dissolving ionic solutes in a polar solvent</h2><p><mark id="ngss-532" class="ngss">Electrolyte drinks also contain NaCl and other <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salts</mark>, which provide <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> your body uses when contracting muscles. These salt <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> have ionic <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark> rather than <mark class="term" data-term="covalent bond" data-term-def="A very strong chemical bond formed by the sharing of a pair of electrons. Multiple covalent bonds can be formed&hellip;" data-term-url="/en/glossary/view/covalent+bond/1550">covalent bonds</mark> and dissolve somewhat differently. Unlike covalent <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compounds</mark>, many <mark class="term" data-term="ionic compound" data-term-def="A chemical compound held together by ionic bonds, that is, electrostatic attraction between positive and negative ions. Ionic compounds generally&hellip;" data-term-url="/en/glossary/view/ionic+compound/1546">ionic compounds</mark> break into their constituent <mark class="term" data-term="ion" data-term-url="/en/glossary/view/ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;">ions</mark> in water. When the NaCl in the drink mix interacts with water, for example, the <mark class="term" data-term="ionic bond" data-term-def="A chemical bond characterized by electrostatic attraction between ions of opposite charge. The formation of an ionic bond involves a&hellip;" data-term-url="/en/glossary/view/ionic+bond/1545">ionic bonds</mark> between the Na<sup>+</sup> and Cl<sup>-</sup> ions are broken and the ions separate. They become distributed randomly and evenly throughout the <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>. The surrounding water molecules form <mark class="term" data-term="hydrogen bond" data-term-def="A strong dipole-dipole attraction between two or more molecules, at least one of which has a hydrogen atom bonded to an&hellip;" data-term-url="/en/glossary/view/hydrogen+bond/1560">hydrogen bonds</mark> with the ions, which keeps the ions separated from each other.</mark></p>  <div class="figure"> <figure> <button class="lightbox-button" data-lightbox-src="/img/library/large_images/image_11753.jpg" data-lightbox="image"> <img src="/img/library/modules/mid266/Image/VLObject-11753-171015041023.jpg" alt="Figure 3: NaCl in water - the ionic bonds between the Na+ and Cl- ions are broken and the ions separate. The surrounding water molecules form hydrogen bonds with the ions." /> </button> <figcaption> <p><strong>Figure 3</strong>: NaCl in water - the ionic bonds between the Na<sup>+</sup> and Cl<sup>-</sup> ions are broken and the ions separate. The surrounding water molecules form hydrogen bonds with the ions.</p> <span class="credit">image ©Ahazard.sciencewriter</span> </figcaption> </figure> </div> <p>For all covalent and ionic <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compounds</mark>, the arrangement of water <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> around the <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> keeps the solute from coming together again to form a solid—in other words, it’s what keeps the solute dissolved. Therefore, the ability for these compounds to dissolve in water relies on <mark class="term" data-term="charge" data-term-def="A quantity of electricity." data-term-url="/en/glossary/view/charge/8258">charge</mark> and <mark class="term" data-term="polarity" data-term-def="The directionality of a magnetic field, which consists of a north and south pole of equal and opposite strength. Lines of&hellip;" data-term-url="/en/glossary/view/polarity/2877">polarity</mark>.</p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form name="cc11881"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">When NaCl dissolves in water, _____.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-11881-0-option-a" name="quiz-option-11881" type="radio" value="the salt molecule separates into component ions" > <span class="option__label"> <span class="screen-reader-only">a.</span> the salt molecule separates into component ions </span> </label> <span class="quiz__response" id="response-11881-0"> <strong>Correct!</strong> </span> </div> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-11881-1-option-b" name="quiz-option-11881" type="radio" value="the salt molecule stays intact" > <span class="option__label"> <span class="screen-reader-only">b.</span> the salt molecule stays intact </span> </label> <span class="quiz__response" id="response-11881-1"> <strong>Incorrect.</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_4"> <h2>Dissolving nonpolar solutes in a nonpolar solvent</h2><p><mark id="ngss-533" class="ngss">Nonpolar <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solutes</mark> also dissolve in nonpolar <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solutions</mark> without breaking any <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark> within the <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecule</mark>. For example, if you’re cooking, you can add some walnut oil to your olive oil for extra flavor. The molecules of walnut oil will mix in and become dispersed among the molecules of olive oil. As with <mark class="term" data-term="polar" data-term-def="Carrying an electrical charge." data-term-url="/en/glossary/view/polar/8730">polar</mark> solutions, the <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark> molecules surround the solute molecules, but the attraction behind it is London dispersion <mark class="term" data-term="force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;" data-term-url="/en/glossary/view/force/883">forces</mark> (LDFs), rather than hydrogen <mark class="term" data-term="bonding" data-term-def="The act of fastening two atoms together." data-term-url="/en/glossary/view/bonding/8295">bonding</mark> or ion-dipole interactions. LDFs are temporary <mark class="term" data-term="force" data-term-url="/en/glossary/view/force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;">forces</mark> formed when the <mark class="term" data-term="electron" data-term-def="A subatomic particle with a negative charge of 1.60 × 10<sup>-19</sup> coulombs and a mass of 9.11 × 10<sup>-31</sup> kg. Electrons&hellip;" data-term-url="/en/glossary/view/electron/852">electrons</mark> across two nearby <mark class="term" data-term="atom" data-term-def="The smallest unit of an element that retains the chemical properties of the element. Atoms can exist alone or in&hellip;" data-term-url="/en/glossary/view/atom/1509">atoms</mark> are unevenly distributed, resulting in a fleeting dipole-to-dipole attraction between the nearby atoms. These temporary attractive forces account for the dissolution of non-polar solutes in non-polar solvents.</mark> (See our <a href="/library/module_viewer.php?mid=222">Properties of Liquids</a> module for more on <mark class="term" data-term="intermolecular force" data-term-def="A force that is exerted <em>between</em> neighboring molecules, as opposed to the forces that are exerted within individual molecules to keep&hellip;" data-term-url="/en/glossary/view/intermolecular+force/7478">intermolecular forces</mark>.)</p><p><mark id="ngss-534" class="ngss">Because LDFs are much weaker and temporary compared to hydrogen <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark>, a non-polar <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> will be much less likely to dissolve in water (or another <mark class="term" data-term="polar" data-term-def="Carrying an electrical charge." data-term-url="/en/glossary/view/polar/8730">polar</mark> substance). The LDFs between the non-polar solute and the polar <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark> <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> are not strong enough to break the <mark class="term" data-term="hydrogen bond" data-term-def="A strong dipole-dipole attraction between two or more molecules, at least one of which has a hydrogen atom bonded to an&hellip;" data-term-url="/en/glossary/view/hydrogen+bond/1560">hydrogen bonds</mark> between water molecules (or other polar solvents). Thus, nonpolar solutes generally dissolve very little, if at all in polar solvents, and the opposite is also true.</mark></p><p><mark id="ngss-535" class="ngss">This difference in <mark class="term" data-term="solubility" data-term-def="The extent to which a solid dissolves in a particular solvent." data-term-url="/en/glossary/view/solubility/7572">solubility</mark> is often characterized by the phrase "like dissolves like." You can see this principle at work when you make salad dressing. Imagine you take your olive oil <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> and mix it with a <mark class="term" data-term="polar" data-term-def="Carrying an electrical charge." data-term-url="/en/glossary/view/polar/8730">polar</mark> vinegar solution. You need to shake the dressing to mix it, and after a few minutes, the polar and nonpolar parts separate. That’s because vinegar is a solution of water and polar acetic <mark class="term" data-term="acid" data-term-def="Generally, a substance that reacts with bases to form a salt, several different definitions of acids have been proposed by different&hellip;" data-term-url="/en/glossary/view/acid/1573">acid</mark>. The polar acetic acid and water <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> create hydrogen <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark> with each other, but not with the nonpolar oil molecules. The oil <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> are, in a sense, left out by the fact that they’re not charged, and coalesce on their own, separate from the vinegar.</mark></p>  <div class="figure"> <figure> <button class="lightbox-button" data-lightbox-src="/img/library/large_images/image_11754.jpg" data-lightbox="image"> <img src="/img/library/modules/mid266/Image/VLObject-11754-171015041047.jpg" alt="Figure 4: The difference in solubility of oil and water, separating into polar and nonpolar parts." /> </button> <figcaption> <p><strong>Figure 4</strong>: The difference in solubility of oil and water, separating into polar and nonpolar parts.</p> <span class="credit">image ©Victor Blacus</span> </figcaption> </figure> </div> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form name="cc11811"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">Nonpolar solutes dissolve more readily in _____ solutions.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-11811-0-option-a" name="quiz-option-11811" type="radio" value="polar" > <span class="option__label"> <span class="screen-reader-only">a.</span> polar </span> </label> <span class="quiz__response" id="response-11811-0"> <strong>Incorrect.</strong> </span> </div> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-11811-1-option-b" name="quiz-option-11811" type="radio" value="nonpolar" > <span class="option__label"> <span class="screen-reader-only">b.</span> nonpolar </span> </label> <span class="quiz__response" id="response-11811-1"> <strong>Correct!</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_5"> <h2>Dissolving involves energy</h2><p><mark id="ngss-536" class="ngss">The <mark class="term" data-term="process" data-term-def="Method, procedure; series of actions or steps." data-term-url="/en/glossary/view/process/8256">process</mark> of dissolving always involves a change in <mark class="term" data-term="energy" data-term-def="An abstract property defined as the capacity to do work. The basic forms of energy include chemical, electrical, mechanical, nuclear, and&hellip;" data-term-url="/en/glossary/view/energy/1497">energy</mark> because of the <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark> and intermolecular <mark class="term" data-term="force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;" data-term-url="/en/glossary/view/force/883">forces</mark> that are being broken and formed. This might mean that the <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> needs to <mark class="term" data-term="absorb" data-term-def="Take in or soak up (energy, liquids, or other substances), usually gradually, through a chemical or physical action." data-term-url="/en/glossary/view/absorb/11219">absorb</mark> energy from its <mark class="term" data-term="environment" data-term-def="The conditions that surround and affect an organism." data-term-url="/en/glossary/view/environment/8270">environment</mark>, or it can also give off energy. Take, for example, a couple of common household items: baking soda, otherwise known as sodium bicarbonate, or NaHO<sub>3</sub>, and sodium carbonate, Na<sub>2</sub>CO<sub>3</sub>, a common ingredient in dishwashing powder. You can add a bit of either of these to a glass of water, and it will disappear. What might not be obvious is that when you dissolve the sodium bicarbonate, the water warms up slightly. And when you add the sodium carbonate, the water cools slightly. This is because dissolution of the baking soda results in a net release of energy, this energy flows into the <mark class="term" data-term="system" data-term-def="A group of interacting, interrelated or interdependent components that form a complex whole. The size of the system is defined for&hellip;" data-term-url="/en/glossary/view/system/3904">system</mark> and warms the water. Dissolving sodium carbonate requires energy – thus cooling off the solution by absorbing energy from it.</mark></p></section> <section id="toc_6"> <h2>Molarity: How much solute is in the solution?</h2><p>Knowing what a <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> is on a molecular level still doesn’t tell us how many <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> or <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> are dissolved in it. For that, we need to know the <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark>, or number, of <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> in a given <mark class="term" data-term="volume" data-term-def="The amount of space taken up by matter, commonly expressed in cubic centimeters (cm<sup>3</sup>) or milliliters (ml)." data-term-url="/en/glossary/view/volume/8515">volume</mark> of the solution.</p><p>Let’s return to the example of <mark class="term" data-term="electrolyte" data-term-def="A substance that dissociates into 2 or more oppositely charged ions in water. Electrolytic solutions conduct electricity because the charged&hellip;" data-term-url="/en/glossary/view/electrolyte/1562">electrolyte</mark> drink mix, but this time, let’s say you want to make your own (much cheaper!). You’re going to use <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> for <mark class="term" data-term="energy" data-term-def="An abstract property defined as the capacity to do work. The basic forms of energy include chemical, electrical, mechanical, nuclear, and&hellip;" data-term-url="/en/glossary/view/energy/1497">energy</mark> and table <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark>, or NaCl for some of the electrolytes. The ideal flavor would be a sort of equal balance between sweet and salty. So, you weigh out 100g of glucose and 100g of NaCl, add them to your pitcher, and fill it up till you’ve got a liter. You give it a taste and discover it’s terribly salty. How did that happen when you added the same amount of each?</p><p><mark id="ngss-537" class="ngss">The answer is that, while you added the same <mark class="term" data-term="weight" data-term-def="A measure of the force exerted on an object by a gravitational field. The weight of an object equals its mass&hellip;" data-term-url="/en/glossary/view/weight/3418">weight</mark> of each <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark>, you didn’t add the same number of <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark>. To know the number of particles, we need to convert to <mark class="term" data-term="mole" data-term-def="An amount equal to Avogadro's number, or 6.02 × 10<sup>23</sup>. One mole of atoms is equal to 6.02 × 10<sup>23</sup> atoms." data-term-url="/en/glossary/view/mole/1515">moles</mark>.</mark></p><p>As described in the <a href="/library/module_viewer.php?mid=53">The Mole and Atomic Mass</a> module, a <mark class="term" data-term="mole" data-term-def="An amount equal to Avogadro's number, or 6.02 × 10<sup>23</sup>. One mole of atoms is equal to 6.02 × 10<sup>23</sup> atoms." data-term-url="/en/glossary/view/mole/1515">mole</mark> is a specific number of <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> of a substance — 6.022 x 10<sup>23</sup> particles, to be exact. The mole is a good <mark class="term" data-term="unit" data-term-def="An accepted quantity used as a standard of measurement. For example, the meter, liter, and gram." data-term-url="/en/glossary/view/unit/848">unit</mark> for describing how many particles are in a <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>, regardless of how much each particle weighs. Usually, when we are measuring quantities of a chemical, we just need to know the fraction of a mole we are using, rather than the exact number of particles.</p><p>Let’s see how this works out with our <mark class="term" data-term="electrolyte" data-term-def="A substance that dissociates into 2 or more oppositely charged ions in water. Electrolytic solutions conduct electricity because the charged&hellip;" data-term-url="/en/glossary/view/electrolyte/1562">electrolyte</mark> drink. One <mark class="term" data-term="mole" data-term-def="An amount equal to Avogadro's number, or 6.02 × 10<sup>23</sup>. One mole of atoms is equal to 6.02 × 10<sup>23</sup> atoms." data-term-url="/en/glossary/view/mole/1515">mole</mark> of <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> ($C_6H_{12}O_6$) weighs 180 g. So to find the fraction of a mole we have, recall from the Moles unit:</p><div class="figure"><figure> $$\frac{Sample \, mass \, (g)}{Sample's \, molar \, mass(\frac{g}{mol})} = Moles \, in \, sample \, (mol)$$ <figcaption><strong>Equation 1a</strong></figcaption> </figure></div><p>Doing the calculation:</p><div class="figure"><figure> $$\frac{100g \, glucose}{180(\frac{g \, glucose}{mol})} = 0.55 \, mol \, glucose$$ <figcaption><strong>Equation 1b</strong></figcaption> </figure></div><p>Doing the same for NaCl, which has a molar <mark class="term" data-term="mass" data-term-def="A fundamental property of matter which is a numerical measure of the inertia of an object or the amount of matter&hellip;" data-term-url="/en/glossary/view/mass/3417">mass</mark> of 58 g/mol:</p><div class="figure"><figure> $$\frac{100g \, NaCl}{58(\frac{g \, NaCl}{mol})} = 1.7mol \, NaCl$$ <figcaption><strong>Equation 1c</strong></figcaption> </figure></div><p>As you can see, you’ve added over three times more <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> than <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark>. No wonder it doesn’t taste so good!</p><p>Measuring <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> using <mark class="term" data-term="mole" data-term-def="An amount equal to Avogadro's number, or 6.02 × 10<sup>23</sup>. One mole of atoms is equal to 6.02 × 10<sup>23</sup> atoms." data-term-url="/en/glossary/view/mole/1515">moles</mark> per liter (moles/L) is more useful in chemistry than using grams per liter because it tells you how many <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> of a substance you’re dealing with. We call the measure of moles per liter of <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> the molarity. A solution with 0.5 moles of <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> per liter of water is a 0.5 M (M is for “molar”) glucose solution. Your solution is also a 1.7 M NaCl solution.</p><p>Let’s say you try to get rid of some excess NaCl by pouring out half of the <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>. Well, you’ll be disappointed. You may have gotten rid of half of your NaCl <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark>, but you’ve also got only have the <mark class="term" data-term="volume" data-term-def="The amount of space taken up by matter, commonly expressed in cubic centimeters (cm<sup>3</sup>) or milliliters (ml)." data-term-url="/en/glossary/view/volume/8515">volume</mark> of water. The <mark class="term" data-term="ratio" data-term-def="The relationship between two or more quantities; relative amounts of two or more values expressed as a proportion." data-term-url="/en/glossary/view/ratio/8556">ratio</mark> of <mark class="term" data-term="ion" data-term-url="/en/glossary/view/ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;">ions</mark> to water remains the same, therefore your <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> of NaCl remains the same.</p><div class="figure"><figure> $$\frac{1.7 mol}{1 L} = \frac{0.85 mol}{0.5 L}$$ <figcaption><strong>Equation 2</strong></figcaption> </figure></div><p>This would be true for the <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> as well:</p><div class="figure"><figure> $$\frac{0.5 mol}{1 L} = \frac{0.25 mol}{0.5 L}$$ <figcaption><strong>Equation 3</strong></figcaption> </figure></div> <div class="container margin-y-4 text-align-center"> <script async src="https://pagead2.googlesyndication.com/pagead/js/adsbygoogle.js?client=ca-pub-9561344156007092" crossorigin="anonymous"></script>  <ins class="adsbygoogle" style="display:inline-block;width:300px;height:250px" data-ad-client="ca-pub-9561344156007092" data-ad-slot="3321739899"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> <p>To add equal amounts of <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> and NaCl, you’d need to add the same fraction of <mark class="term" data-term="mole" data-term-def="An amount equal to Avogadro's number, or 6.02 × 10<sup>23</sup>. One mole of atoms is equal to 6.02 × 10<sup>23</sup> atoms." data-term-url="/en/glossary/view/mole/1515">moles</mark> to the liter of water. Let’s say you want to add a half a mole of each:</p><div class="figure"><figure> $$0.5mol \, glucose \times \frac{180g}{1mol} = 90g \, glucose$$ <figcaption><strong>Equation 4a</strong></figcaption> </figure></div><div class="figure"><figure> $$0.5mol \, NaCl \, \times \, \frac{58g}{1mol} = 29g \, glucose$$ <figcaption><strong>Equation 4b</strong></figcaption> </figure></div><p>There is a big difference in <mark class="term" data-term="weight" data-term-def="A measure of the force exerted on an object by a gravitational field. The weight of an object equals its mass&hellip;" data-term-url="/en/glossary/view/weight/3418">weight</mark>, but if you added 90g of <mark class="term" data-term="glucose" data-term-def="The primary form of sugar stored in the human body for energy: C<sub>6</sub>H<sub>12</sub>O<sub>6</sub>." data-term-url="/en/glossary/view/glucose/8735">glucose</mark> and 29g of <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> you would have an equal number of <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark>. This example gives you an idea of why chemists use molarity, mol/L, to describe the <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> of <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solutions</mark>.</p><p>It’s worth noting that, while you add 0.5 <mark class="term" data-term="mole" data-term-def="An amount equal to Avogadro's number, or 6.02 × 10<sup>23</sup>. One mole of atoms is equal to 6.02 × 10<sup>23</sup> atoms." data-term-url="/en/glossary/view/mole/1515">mole</mark> of NaCl, once the <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> dissolves and the Na<sup>+</sup> and Cl<sup>-</sup> <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> have separated from each other, you will have 0.5 mole of each of them in the <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>. In other words, you will have 1.0 mol of <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark>, half of them being Na<sup>+</sup> and the other half being Cl<sup>-</sup>. This can be important when you’re calculating the total molarity of a solution you create.</p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form name="cc11812"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">Molarity is measured in _____ per liter.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-11812-0-option-a" name="quiz-option-11812" type="radio" value="grams" > <span class="option__label"> <span class="screen-reader-only">a.</span> grams </span> </label> <span class="quiz__response" id="response-11812-0"> <strong>Incorrect.</strong> </span> </div> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-11812-1-option-b" name="quiz-option-11812" type="radio" value="moles" > <span class="option__label"> <span class="screen-reader-only">b.</span> moles </span> </label> <span class="quiz__response" id="response-11812-1"> <strong>Correct!</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_7"> <h2>Solubility: A balance of forces</h2><p>Some <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compounds</mark>, such as NaCl dissolve easily in water—pour a teaspoon in a glass of water, stir, and it’s dissolved. The ability of a compound to dissolve in water is called <mark class="term" data-term="solubility" data-term-def="The extent to which a solid dissolves in a particular solvent." data-term-url="/en/glossary/view/solubility/7572">solubility</mark>. Some substances are much more <mark class="term" data-term="soluble" data-term-def="Capable of being dissolved." data-term-url="/en/glossary/view/soluble/8532">soluble</mark> in water than others. The solubility of a compound arises from the forces at work when adding <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> to water.</p><p>The fact that sodium chloride dissolves so readily in water makes it great for our ion-detecting taste buds. Other types of <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salts</mark> (salts generally are <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compounds</mark> made of a metal and a nonmetal) wouldn’t be nearly as good on your French fries. In silver chloride, AgCl, for example, the <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark> between the two <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> are much stronger. Pour a teaspoon of AgCl into a glass of water, and it will just sit there.</p><p><mark id="ngss-538" class="ngss">To understand why, we can compare what’s happening on the molecular level. In the case of table <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark>, the ionic <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bonds</mark> holding the Na<sup>+</sup> and Cl<sup>-</sup> <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> together are weak enough to be easily broken by attraction to the <mark class="term" data-term="dipole" data-term-def="An asymmetrical distribution of electrical charge across an object. Polar molecules contain a dipole." data-term-url="/en/glossary/view/dipole/1559">dipoles</mark> of the water <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark>, and the <mark class="term" data-term="ion" data-term-url="/en/glossary/view/ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;">ions</mark> separate. Because they are oppositely charged, there is still attraction between them, but they are surrounded by water molecules. The attraction is not enough to draw many of them together in that situation.</mark></p><p><mark id="ngss-539" class="ngss">The <mark class="term" data-term="bond" data-term-def="The force that holds together units such as atoms or molecules. <br> <b>[verb]</b> To hold or fasten units such as atoms or molecules together." data-term-url="/en/glossary/view/bond/8297">bond</mark> between Ag<sup>+</sup> and Cl<sup>-</sup> <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> is stronger, however. So when the silver chloride is in water, few of the <mark class="term" data-term="ionic bond" data-term-def="A chemical bond characterized by electrostatic attraction between ions of opposite charge. The formation of an ionic bond involves a&hellip;" data-term-url="/en/glossary/view/ionic+bond/1545">ionic bonds</mark> will be broken. Even when they are, and when the <mark class="term" data-term="ion" data-term-url="/en/glossary/view/ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;">ions</mark> become surrounded by water <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark>, the pull of Ag<sup>+</sup> and Cl<sup>-</sup> ions toward one another will be great enough to overcome the attraction of the <mark class="term" data-term="polar" data-term-def="Carrying an electrical charge." data-term-url="/en/glossary/view/polar/8730">polar</mark> water molecules.</mark></p><p>In this way, the <mark class="term" data-term="solubility" data-term-def="The extent to which a solid dissolves in a particular solvent." data-term-url="/en/glossary/view/solubility/7572">solubility</mark> of a <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compound</mark> is a balance of the two forces: the attraction between the <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> or <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> of the <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> (which hold the solute together) and the dipole-ion interactions between the solute and water molecules (which keep <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> of solute apart from each other). In the case of AgCl, the interactions between the <mark class="term" data-term="ion" data-term-url="/en/glossary/view/ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;">ions</mark> are stronger than the <mark class="term" data-term="force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;" data-term-url="/en/glossary/view/force/883">forces</mark> that might keep them apart. Most of the AgCl remains ionically bonded as a <mark class="term" data-term="solid" data-term-def="A collection of atoms or molecules that are held together so that, under constant conditions, they maintain a defined shape and&hellip;" data-term-url="/en/glossary/view/solid/7571">solid</mark>. In NaCl, the opposite is true: the attraction between the ions and the surrounding water molecules is stronger than the attractive force between the Na<sup>+</sup> and Cl<sup>-</sup> ions. Most of the NaCl will dissolve into its respective ions.</p>  <div class="figure"> <figure> <button class="lightbox-button" data-lightbox-src="/img/library/large_images/image_11755.jpg" data-lightbox="image"> <img src="/img/library/modules/mid266/Image/VLObject-11755-171015051059.jpg" alt="Figure 5: A traditional way of making salt is to harvest it by allowing the water to evaporate, like these mounds in Salar de Uyuni, Bolivia." /> </button> <figcaption> <p><strong>Figure 5</strong>: A traditional way of making salt is to harvest it by allowing the water to evaporate, like these mounds in Salar de Uyuni, Bolivia.</p> <span class="credit">image ©Luca Galuzzi</span> </figcaption> </figure> </div> <p>This is true up to a point—the <mark class="term" data-term="saturation" data-term-def="the state at which a body or parcel of air has reached its maximum capacity for holding dissolved moisture as water vapor." data-term-url="/en/glossary/view/saturation/12936">saturation</mark> point. As you continue to add more and more NaCl to a <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>, the <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ion</mark> <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentrations</mark> increase and they are packed in closer and closer to each other. Eventually, there will be so many Na<sup>+</sup> and Cl<sup>-</sup> <mark class="term" data-term="ion" data-term-url="/en/glossary/view/ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;">ions</mark>, that some of them will be close enough to each other that the attractive <mark class="term" data-term="force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;" data-term-url="/en/glossary/view/force/883">forces</mark> between them will outdo the <mark class="term" data-term="force" data-term-url="/en/glossary/view/force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;">forces</mark> keeping them apart. The Na<sup>+</sup> and Cl<sup>-</sup> will be drawn back together and reform as a <mark class="term" data-term="solid" data-term-def="A collection of atoms or molecules that are held together so that, under constant conditions, they maintain a defined shape and&hellip;" data-term-url="/en/glossary/view/solid/7571">solid</mark>, leaving undissolved grains of <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> at the bottom of the vessel. (This is, in fact, what happens if you allow the water to evaporate, and the Na<sup>+</sup> and Cl<sup>-</sup> ions become solid NaCl <mark class="term" data-term="crystal" data-term-def="A solid of defined shape that is bound by plane surfaces (facets) that intersect at characteristic angles. The shape of a&hellip;" data-term-url="/en/glossary/view/crystal/1564">crystals</mark> again.) At this point, we say the solution is saturated, meaning that it can’t <mark class="term" data-term="absorb" data-term-def="Take in or soak up (energy, liquids, or other substances), usually gradually, through a chemical or physical action." data-term-url="/en/glossary/view/absorb/11219">absorb</mark> any more <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark>.</p><p>When adding walnut oil to olive oil, as discussed above, the two simply mix together. Once the <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> is more than 50% walnut oil, the olive oil becomes the <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> and the walnut oil the <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark>. We say something is <mark class="term" data-term="miscible" data-term-def="Two substances that can mix completely, such as two liquids combining to form a homogeneous solution." data-term-url="/en/glossary/view/miscible/11758">miscible</mark> when it forms a <mark class="term" data-term="homogeneous mixture" data-term-def="A mixture of two or more substances that cannot be easily separated by common physical means (i.e., settling, filtration, etc.). A&hellip;" data-term-url="/en/glossary/view/homogeneous+mixture/1566">homogeneous mixture</mark> with another substance.</p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form name="cc11882"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">When a solution cannot absorb any more of a solute, it has reached its _____ point.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-11882-0-option-a" name="quiz-option-11882" type="radio" value="concentration" > <span class="option__label"> <span class="screen-reader-only">a.</span> concentration </span> </label> <span class="quiz__response" id="response-11882-0"> <strong>Incorrect.</strong> </span> </div> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-11882-1-option-b" name="quiz-option-11882" type="radio" value="saturation" > <span class="option__label"> <span class="screen-reader-only">b.</span> saturation </span> </label> <span class="quiz__response" id="response-11882-1"> <strong>Correct!</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_8"> <h2>Solubility rules</h2><p>As described earlier, the <mark class="term" data-term="solubility" data-term-def="The extent to which a solid dissolves in a particular solvent." data-term-url="/en/glossary/view/solubility/7572">solubility</mark> of a <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compound</mark> is really the result of the balance of <mark class="term" data-term="force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;" data-term-url="/en/glossary/view/force/883">forces</mark> within and between <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark>. But how do we know the result of that balance for a particular compound? <mark id="ngss-540" class="ngss">Over the years, many different scientists have experimented with solubility, and some predictable patterns have emerged from their work. These patterns have been collected in a set of solubility guidelines (also called solubility rules) that are used to predict whether a compound will dissolve in water.</mark></p><div class='\"figure\"'><table class="table" aria-describedby="configDescription"> <caption id="configDescription"> <strong>Table 1:</strong> Solubility rules for soluble ionic compounds in water </caption> <thead> <tr> <th scope="col">Compounds containing:</th> <th scope="col">Exceptions:</th> </tr> </thead> <tbody> <tr> <td scope="row">$NO_3^-$</td> <td>n/a</td> </tr> <tr> <td scope="row">$C_2H_3O_2^-$</td> <td>n/a</td> </tr> <tr> <td scope="row">$CL^-$</td> <td>$Ag^+ , Hg_2^{2+}, \& \, Pb^{2+}$ compounds</td> </tr> <tr> <td scope="row">$Br^-$</td> <td>$Ag^+ , Hg_2^{2+}, \& \, Pb^{2+}$ compounds</td> </tr> <tr> <td scope="row">$I^-$</td> <td>$Ag^+ , Hg_2^{2+}, \& \, Pb^{2+}$ compounds</td> </tr> <tr> <td scope="row">$SO_4^{2-}$</td> <td>$Sr^{2+} ,Ba^{2+} , Hg_2^{2+}, \& \, Pb^{2+}$ compounds</td> </tr> </tbody> </table></div> <div class='\"figure\"'><table class="table" aria-describedby="configDescription2"> <caption id="configDescription2"> <strong>Table 2:</strong> Solubility rules for insoluble ionic compounds in water </caption> <thead> <tr> <th scope="col">Compounds containing:</th> <th scope="col">Exceptions:</th> </tr> </thead> <tbody> <tr> <td scope="row">$S^{2-}$</td> <td>$NH_4^+$ compounds & alkali metal cations, $Ca^{2+}, \, Sr^{2+}, \, \& \, Ba^{2+}$</td> </tr> <tr> <td scope="row">$CO_3^{2-}$</td> <td>$NH_4^+$ compounds & alkali metal cations</td> </tr> <tr> <td scope="row">$PO_4^{3-}$</td> <td>$NH_4^+$ compounds & alkali metal cations</td> </tr> <tr> <td scope="row">$OH^-$</td> <td>Alkali metal cations compounds, $NH_4^+ , \, Ca^{2+}, \, Sr^{2+}, \& \, Ba^{2+}$</td> </tr> </tbody> </table></div> <p><mark id="ngss-541" class="ngss">These guidelines are very useful for chemical engineers, who are often devising products like fertilizer, drugs, and household goods. Such items are often most efficiently shipped as powders or <mark class="term" data-term="solid" data-term-def="A collection of atoms or molecules that are held together so that, under constant conditions, they maintain a defined shape and&hellip;" data-term-url="/en/glossary/view/solid/7571">solids</mark> but must be able to dissolve in water to be used. Consider powered laundry soap, for example. If it were simply powdered soap, it would get clumpy with changes in humidity. So manufacturers combine it with a naturally dry, flaky substance to prevent clumps and allow it to flow freely. That flaky substance also has to be <mark class="term" data-term="soluble" data-term-def="Capable of being dissolved." data-term-url="/en/glossary/view/soluble/8532">soluble</mark> in water and not leave behind <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> that might react and damage clothing, pipes, or the washer. The most common laundry detergent additive is sodium sulfate (Na<sub>2</sub>SO<sub>4</sub>). You can see from the chart above that all sulfates are soluble in water with the exceptions of those that form one of four different metal <mark class="term" data-term="ion" data-term-url="/en/glossary/view/ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;">ions</mark>.</mark></p><p>The <mark class="term" data-term="solubility" data-term-def="The extent to which a solid dissolves in a particular solvent." data-term-url="/en/glossary/view/solubility/7572">solubility</mark> rules are useful in the other “direction” as well: in other words, let’s say you have two <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solutions</mark>, each with different <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> dissolved in them. The guidelines can help you predict whether mixing those two solutions will cause a <mark class="term" data-term="reaction" data-term-def="A chemical change when substances come into contact with each other." data-term-url="/en/glossary/view/reaction/8263">reaction</mark> that produces an <mark class="term" data-term="insoluble" data-term-def="Unable to be dissolved." data-term-url="/en/glossary/view/insoluble/8732">insoluble</mark> <mark class="term" data-term="solid" data-term-def="A collection of atoms or molecules that are held together so that, under constant conditions, they maintain a defined shape and&hellip;" data-term-url="/en/glossary/view/solid/7571">solid</mark>.</p><p>This could have been useful for the Romans if they’d wanted to get rid of the lead in their water. They would have been able to look at the chart and see that several <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark> will combine with lead to form <mark class="term" data-term="insoluble" data-term-def="Unable to be dissolved." data-term-url="/en/glossary/view/insoluble/8732">insoluble</mark> <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compounds</mark>. An insoluble compound produced in <mark class="term" data-term="reaction" data-term-def="A chemical change when substances come into contact with each other." data-term-url="/en/glossary/view/reaction/8263">reactions</mark> involving aqueous <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solutions</mark> is called a <mark class="term" data-term="precipitate" data-term-def="A solid or otherwise insoluble product that is formed by a chemical reaction occuring in a liquid solution." data-term-url="/en/glossary/view/precipitate/4889">precipitate</mark>.</p><p>Here again, sodium sulfate can come in handy. The <mark class="term" data-term="compound" data-term-def="A material formed by the chemical combination of elements in defined proportions. Compounds can be chemically decomposed into simpler substances." data-term-url="/en/glossary/view/compound/1517">compound</mark> is found in many common rocks, and so the Romans probably had access to it. As you saw above, the <mark class="term" data-term="solubility" data-term-def="The extent to which a solid dissolves in a particular solvent." data-term-url="/en/glossary/view/solubility/7572">solubility</mark> guidelines show that sodium sulfate is <mark class="term" data-term="soluble" data-term-def="Capable of being dissolved." data-term-url="/en/glossary/view/soluble/8532">soluble</mark> in water. They also show that lead sulfate is not. Therefore, adding Na<sub>2</sub>SO<sub>4</sub> to water that contains lead will produce a <mark class="term" data-term="precipitate" data-term-def="A solid or otherwise insoluble product that is formed by a chemical reaction occuring in a liquid solution." data-term-url="/en/glossary/view/precipitate/4889">precipitate</mark> according to the reaction: Pb<sup>2+</sup> <sub>(aq)</sub> + SO<sub>4</sub><sup>2-</sup> <sub>(aq)</sub> → PbSO<sub>4</sub> <sub>(s)</sub></p><p>And indeed, that <mark class="term" data-term="reaction" data-term-def="A chemical change when substances come into contact with each other." data-term-url="/en/glossary/view/reaction/8263">reaction</mark> forms a cloudy white <mark class="term" data-term="precipitate" data-term-def="A solid or otherwise insoluble product that is formed by a chemical reaction occuring in a liquid solution." data-term-url="/en/glossary/view/precipitate/4889">precipitate</mark> of lead sulfate that can be filtered out of the <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>.</p><p>If a Roman chemist wanted to be sure they got rid of all the lead, they would need to know the molarity of lead in the water, and use an appropriate amount of sodium sulfate. Too little would leave dissolved lead behind, and too much would leave a lot of excess Na<sup>+</sup> and SO<sub>4</sub><sup>2-</sup> <mark class="term" data-term="ion" data-term-def="An atom or molecule that has acquired an electrical charge by either gaining or losing electrons. A cation is an ion&hellip;" data-term-url="/en/glossary/view/ion/853">ions</mark>, which could cause corrosion.</p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form name="cc11883"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">Precipitates are _____.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-11883-0-option-a" name="quiz-option-11883" type="radio" value="highly soluble" > <span class="option__label"> <span class="screen-reader-only">a.</span> highly soluble </span> </label> <span class="quiz__response" id="response-11883-0"> <strong>Incorrect.</strong> </span> </div> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-11883-1-option-b" name="quiz-option-11883" type="radio" value="insoluble" > <span class="option__label"> <span class="screen-reader-only">b.</span> insoluble </span> </label> <span class="quiz__response" id="response-11883-1"> <strong>Correct!</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc_9"> <h2>Colligative properties: concentration matters</h2><p>Another reason that knowing the molarity of a <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> is important is that it determines some of the solution’s properties. For example, if you live in a snowy <mark class="term" data-term="climate" data-term-def="Climate describes the average and patterns of a particular area’s weather over time. Climate includes such elements as temperature, precipitation, humidity,&hellip;" data-term-url="/en/glossary/view/climate/9334">climate</mark>, you’ve seen trucks out spreading <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> on icy roads. A little bit of the salt dissolves into the <mark class="term" data-term="surface" data-term-def="The outside or external part; the topside face of something." data-term-url="/en/glossary/view/surface/8275">surface</mark> of the ice and creates a salt solution. This water with salt in it actually has a lower freezing point than water. Over time (and with cars driving over it), the salt dissolves into more and more of the ice, lowering its freezing point and allowing it to melt, creating safer driving conditions.</p>  <div class="figure"> <figure> <button class="lightbox-button" data-lightbox-src="/img/library/large_images/image_11756.jpg" data-lightbox="image"> <img src="/img/library/modules/mid266/Image/VLObject-11756-171015071026.jpg" alt="Figure 6: Phase diagrams of solutions of sodium chloride (NaCl) and calcium chloride (CaCl2) solutions. The calcium chloride-water remains a solution as low as -51°C (-60°F), whereas the sodium chloride-water freezes at about -21°C (-6°F)." /> </button> <figcaption> <p><strong>Figure 6</strong>: Phase diagrams of solutions of sodium chloride (NaCl) and calcium chloride (CaCl<sub>2</sub>) solutions. The calcium chloride-water remains a solution as low as -51°C (-60°F), whereas the sodium chloride-water freezes at about -21°C (-6°F).</p> <span class="credit">image ©Federal Highway Administration</span> </figcaption> </figure> </div> <p><mark id="ngss-542" class="ngss">If you said that having more <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> dissolved in the water is what caused this change in freezing point, you’d be correct, but not exactly correct. It’s not actually the <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> of <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> that matters, but the concentration of <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark>. And as more salt dissolves in the water, the concentration of salt goes up and the concentration of water goes down. IIt’s this shift in the concentration of water that changes the properties of the <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>. A less concentrated solvent will have a lower freezing point, and higher boiling point, and a lower vapor pressure. We call these properties that are affected by concentration colligative properties, (from the Latin words <em>co</em> – "together" – and <em>ligare</em> – "bind"). Colligative properties often relate to a state change, either from <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark> to <mark class="term" data-term="solid" data-term-def="A collection of atoms or molecules that are held together so that, under constant conditions, they maintain a defined shape and&hellip;" data-term-url="/en/glossary/view/solid/7571">solid</mark> or liquid to <mark class="term" data-term="gas" data-term-def="The state of matter characterized by its non-condensed nature and ability to flow. Unlike liquids, molecules within a gas remain far&hellip;" data-term-url="/en/glossary/view/gas/8725">gas</mark>.</mark> (See the <a href="/library/module_viewer.php?mid=120">States of Matter</a> module for more on state change.)</p><p>Because these properties actually depend on the <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> of <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark>, it doesn’t matter what <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> is added. If you find that a bit confusing, you’re in good company. It took some very bright chemists about five decades to explain it.</p></section> <section id="toc2_1"><h3>Freezing point depression</h3><p>In the early 1700s, the Swiss physicist chemist <mark class="term" data-term="Daniel Bernoulli" data-term-def="Swiss medical doctor and mathematician born in Groningen (1700-1782). His work <em>Hydrodynamica</em> contains the first correct analysis of the dynamics of&hellip;" data-term-url="/en/glossary/view/Bernoulli%2C+Daniel/4482">Daniel Bernoulli</mark> noted that concentrated <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> and <mark class="term" data-term="sugar" data-term-def="A water-soluble crystalline carbohydrate. There are many types of sugar of varying degrees of sweetness, including fructose, which occurs naturally in&hellip;" data-term-url="/en/glossary/view/sugar/5309">sugar</mark> <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solutions</mark> seemed to freeze at lower temperatures than pure water. He postulated that the <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> in water somehow reduced the attractive <mark class="term" data-term="force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;" data-term-url="/en/glossary/view/force/883">forces</mark> between the water <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark>, keeping the water from freezing until it had reached a lower temperature. He was curious about the phenomenon, but busy with other <mark class="term" data-term="experiment" data-term-def="A test or trial carried out under controlled conditions so that specific actions can be performed and the results can be observed." data-term-url="/en/glossary/view/experiment/8292">experiments</mark> and didn’t pursue it further.</p><p>Some years later the English chemist Richard Watson, a follower of Bernoulli, also became curious about this phenomenon and wanted to <mark class="term" data-term="quantify" data-term-def="To express something in terms of a number value, measurement, or amount." data-term-url="/en/glossary/view/quantify/8237">quantify</mark> it. Does the freezing point shift in relation to which <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> you add and how much of it? This wasn’t a simple question to answer given that there was no refrigeration in the 18th century. Scientists at the time depended on the cold, snowy conditions of European winter.</p><p><mark id="ngss-543" class="ngss">Watson got a lucky break on February 12, 1771, when the temperature in his hometown of Cambridge plummeted to -14C. The resourceful chemist took advantage of this rare opportunity, and, no doubt shivering, tested the freezing points of 18 different <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark> <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solutions</mark>. His <mark class="term" data-term="observation" data-term-def="1. The act of noticing something. 2. A record of that which has been noticed." data-term-url="/en/glossary/view/observation/8255">observations</mark> showed that the freezing point of a solution shifts downward in a way that varies with the <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark>, regardless of the <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> involved. This was a big step toward understanding freezing point depression, but Watson wasn’t able to definitively <mark class="term" data-term="quantify" data-term-def="To express something in terms of a number value, measurement, or amount." data-term-url="/en/glossary/view/quantify/8237">quantify</mark> the relationship.</mark></p><p>One of his contemporaries, Charles Blagden, carried out similar <mark class="term" data-term="experiment" data-term-def="A test or trial carried out under controlled conditions so that specific actions can be performed and the results can be observed." data-term-url="/en/glossary/view/experiment/8292">experiments</mark> on samples of water mixed with varying amounts of NaCl. Blagden, however, did not have the advantage of a particularly cold day, so he relied on snow and ice to chill his <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solutions</mark>. <mark id="ngss-544" class="ngss">Blagden confirmed that the relationship between <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> and freezing point was inversely proportional. In other words, the higher the concentration of <mark class="term" data-term="salt" data-term-def="Generally, any ionic compound except those that contain hydroxide or hydrogen ions. Specifically, any compound other than water formed by&hellip;" data-term-url="/en/glossary/view/salt/1575">salt</mark>, the lower the freezing point. Because Blagden was making <mark class="term" data-term="observation" data-term-def="1. The act of noticing something. 2. A record of that which has been noticed." data-term-url="/en/glossary/view/observation/8255">observations</mark> on only one salt (as opposed to many, as Watson had done), he was able to come up with a precise determination of how concentration affects the lowering of the freezing point. His discovery, which can be described mathematically using several different equations, is known as Blagden’s Law. Blagden’s Law quantifies what scientists before him had suspected—the presence of <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> makes it harder for a <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark> to coalesce and form a <mark class="term" data-term="solid" data-term-def="A collection of atoms or molecules that are held together so that, under constant conditions, they maintain a defined shape and&hellip;" data-term-url="/en/glossary/view/solid/7571">solid</mark>, and that forming a solid becomes harder in a way that’s regular and predictable.</mark></p><p><mark id="ngss-545" class="ngss">While it’s easier to express this variation in terms of how many <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> there are, it’s important to remember that the number of solute particles, in turn, determines the number of <mark class="term" data-term="solvent" data-term-def="The most abundant component in a homogeneous mixture of two or more substances." data-term-url="/en/glossary/view/solvent/1565">solvent</mark> particles and that it’s actually the <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> of solvent we’re concerned about. We can explain this phenomenon at the molecular level by considering that when <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark> water freezes, its particles come together in a regular, lattice-like arrangement. If all the particles are the same, it’s relatively easy for a regular <mark class="term" data-term="lattice" data-term-def="A characteristic pattern formed by the spatial distribution of repeating units." data-term-url="/en/glossary/view/lattice/1549">lattice</mark> to form. But when there are solute particles dissolved in the water, the water <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> are bumping into them, and therefore less likely to interact with each other. As the temperature cools, particles slow down and the attraction between water molecules becomes greater than the disruptive <mark class="term" data-term="force" data-term-def="An influence (a "push or pull") that changes the motion of a moving object (e.g., slows it down, speeds it up,&hellip;" data-term-url="/en/glossary/view/force/883">force</mark> of the solute.</mark> </p><p><mark id="ngss-546" class="ngss">Early American colonists cleverly used colligative properties to their advantage when making fermented apple cider (provided they had a cold winter day). They could ferment apple juice until they had a dilute <mark class="term" data-term="alcohol" data-term-def="An organic compound containing a hydroxyl group. Common examples include methanol (CH<sub>3</sub>OH) and ethanol (CH<sub>3</sub>CH<sub>2</sub>OH)." data-term-url="/en/glossary/view/alcohol/1592">alcohol</mark> <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>. If they then set the fermented juice outside in the cold, pure water would freeze out of the solution. The fermented juice, with all that water removed, had a higher <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> of alcohol. Pour the solution out from the ice, and they had a drink called “apple jack,” so named because the freezing <mark class="term" data-term="process" data-term-def="Method, procedure; series of actions or steps." data-term-url="/en/glossary/view/process/8256">process</mark> “jacked” up the concentration of alcohol.</mark></p> <div class="comprehension-checkpoint margin-y-4"> <h6 class="comprehension-checkpoint__header"> <span> <span class="icon icon-question"></span> </span> Comprehension Checkpoint </h6> <form name="cc11884"> <div class="form-entry"> <div class="form-entry__field"> <span class="form-entry__field__label">A higher concentration of solute molecules makes it _____ for a solution to freeze into a solid.</span> <div class="form-entry__option"> <div class="form-entry__option__radio" data-answer="incorrect"> <label> <input id="q1-11884-0-option-a" name="quiz-option-11884" type="radio" value="easier" > <span class="option__label"> <span class="screen-reader-only">a.</span> easier </span> </label> <span class="quiz__response" id="response-11884-0"> <strong>Incorrect.</strong> </span> </div> <div class="form-entry__option__radio" data-answer="correct"> <label> <input id="q1-11884-1-option-b" name="quiz-option-11884" type="radio" value="harder" > <span class="option__label"> <span class="screen-reader-only">b.</span> harder </span> </label> <span class="quiz__response" id="response-11884-1"> <strong>Correct!</strong> </span> </div> </div> </div> </div> </form> </div> </section> <section id="toc2_2"><h3>Vapor pressure lowering and boiling point elevation</h3><p><mark id="ngss-547" class="ngss">Solute <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> affects not only freezing point of a <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> but also its boiling point and vapor pressure. Vapor pressure is a measure of the pressure created at the <mark class="term" data-term="surface" data-term-def="The outside or external part; the topside face of something." data-term-url="/en/glossary/view/surface/8275">surface</mark> of a <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark> as <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> of liquid evaporate. In any liquid in an open container, a small number of the molecules on the surface gain enough <mark class="term" data-term="kinetic" data-term-def="Relating to the motion of objects." data-term-url="/en/glossary/view/kinetic/8681">kinetic</mark> <mark class="term" data-term="energy" data-term-def="An abstract property defined as the capacity to do work. The basic forms of energy include chemical, electrical, mechanical, nuclear, and&hellip;" data-term-url="/en/glossary/view/energy/1497">energy</mark> to escape the liquid and become <mark class="term" data-term="gas" data-term-def="The state of matter characterized by its non-condensed nature and ability to flow. Unlike liquids, molecules within a gas remain far&hellip;" data-term-url="/en/glossary/view/gas/8725">gas</mark>. The more <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> that escape, the higher the vapor pressure. For example, rubbing <mark class="term" data-term="alcohol" data-term-def="An organic compound containing a hydroxyl group. Common examples include methanol (CH<sub>3</sub>OH) and ethanol (CH<sub>3</sub>CH<sub>2</sub>OH)." data-term-url="/en/glossary/view/alcohol/1592">alcohol</mark> evaporates more quickly than water, and therefore has a higher vapor pressure.</mark></p><p>In a container of pure water, the entire <mark class="term" data-term="surface" data-term-def="The outside or external part; the topside face of something." data-term-url="/en/glossary/view/surface/8275">surface</mark> of the <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark> is made up of water <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark>, some of which are evaporating. When <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> <mark class="term" data-term="particle" data-term-def="A tiny piece of matter." data-term-url="/en/glossary/view/particle/8259">particles</mark> are mixed in to create a <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark>, however, those particles take up "real estate," and leave less room for water molecules on the surface. Fewer water molecules on the surface means fewer water molecules evaporating, which reduces the vapor pressure.</p><p>Vapor pressure is related to temperature, in that the warmer the <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark>, the more <mark class="term" data-term="molecule" data-term-def="A particle formed by the chemical bonding of two or more atoms. The molecule is the smallest particle of a&hellip;" data-term-url="/en/glossary/view/molecule/1518">molecules</mark> have enough <mark class="term" data-term="kinetic" data-term-def="Relating to the motion of objects." data-term-url="/en/glossary/view/kinetic/8681">kinetic</mark> <mark class="term" data-term="energy" data-term-def="An abstract property defined as the capacity to do work. The basic forms of energy include chemical, electrical, mechanical, nuclear, and&hellip;" data-term-url="/en/glossary/view/energy/1497">energy</mark> to leave the liquid phase and become <mark class="term" data-term="gas" data-term-def="The state of matter characterized by its non-condensed nature and ability to flow. Unlike liquids, molecules within a gas remain far&hellip;" data-term-url="/en/glossary/view/gas/8725">gas</mark>. As mentioned above, more molecules evaporating translates to a higher vapor pressure. As <mark class="term" data-term="heat" data-term-def="A measure of the total internal energy of a substance that can be increased or decreased when objects with different temperatures&hellip;" data-term-url="/en/glossary/view/heat/1506">heat</mark> is added, eventually a <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> reaches its boiling point. At the boiling point, there are so many molecules with enough <mark class="term" data-term="kinetic energy" data-term-def="The energy an object possesses by virtue of its motion. An object of mass m moving at velocity v has a&hellip;" data-term-url="/en/glossary/view/kinetic+energy/1505">kinetic energy</mark> to become gas that the vapor pressure is equal to the surrounding atmospheric pressure.</p><p>Therefore, it makes sense that because <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solute</mark> <mark class="term" data-term="concentration" data-term-def="The amount of one substance in relation to other components within a given area." data-term-url="/en/glossary/view/concentration/8733">concentration</mark> affects vapor pressure, it also affects boiling point. If the vapor pressure of a <mark class="term" data-term="liquid" data-term-def="The state of matter characterized by its condensed nature and ability to flow. Unlike gases, molecules within a liquid often experience&hellip;" data-term-url="/en/glossary/view/liquid/8727">liquid</mark> is lower in the presence of solute, then getting to the boiling point will require more <mark class="term" data-term="energy" data-term-def="An abstract property defined as the capacity to do work. The basic forms of energy include chemical, electrical, mechanical, nuclear, and&hellip;" data-term-url="/en/glossary/view/energy/1497">energy</mark> or a higher temperature. This phenomenon is known as boiling point elevation.</p><p><mark id="ngss-548" class="ngss">Antifreeze in cars takes advantage of colligative properties to keep your engine at the right temperature. True to its name, <mark class="term" data-term="solute" data-term-def="A compound dissolved in a solvent to create a solution." data-term-url="/en/glossary/view/solute/8729">solutes</mark> in the antifreeze <mark class="term" data-term="solution" data-term-def="A mixture of more than one substance with properties that do not vary within the sample. Commonly used to describe a&hellip;" data-term-url="/en/glossary/view/solution/1571">solution</mark> lower the freezing point and keep the antifreeze (and your engine) from freezing up on very cold days. Those same solutes raise the boiling point, keeping your car from overheating on a hot drive through the desert.</mark></p></section> <footer class="module__main__footer"> <hr class="border-color-dark"> <p class="citation"> <em> Robin Marks, M.A., Anthony Carpi, Ph.D. “Solutions” Visionlearning Vol. CHE-4 (5), 2017. </em> </p>  <div class="title-list" name="further"> <p class="h6 title-list__title"> Further Reading </p> <ul class="grid grid--column-2--md grid--column-3--md gap-1"> <li> <a class="no-hover-focus height-100" href="/en/library/Chemistry/1/States-of-Matter/120"> <article class="flex-row align-items-center flex-column--md align-items-start--md height-100 theme-light padding-2 gap-2"> <div class="width-30 width-auto--md"> <img class="border-radius box-shadow-1" src="/img/library/moduleImages/featured_image_120-23061209064654.jpg" alt="States of Matter"> </div> <div class="flex-grow-shrink"> <h2 class="h6 font-weight-normal"> States of Matter: <em>Kinetic molecular theory and phase transitions</em> </h2> </div> </article> </a> </li> <li> <a class="no-hover-focus height-100" href="/en/library/Chemistry/1/Properties-of-Gases/245"> <article class="flex-row align-items-center flex-column--md align-items-start--md height-100 theme-light padding-2 gap-2"> <div class="width-30 width-auto--md"> <img class="border-radius box-shadow-1" src="/img/library/moduleImages/featured_image_245-23061209064749.jpeg" alt="Properties of Gases"> </div> <div class="flex-grow-shrink"> <h2 class="h6 font-weight-normal"> Properties of Gases: <em>The gas laws and the ideal gas equation</em> </h2> </div> </article> </a> </li> <li> <a class="no-hover-focus height-100" href="/en/library/Chemistry/1/Properties-of-Liquids/222"> <article class="flex-row align-items-center flex-column--md align-items-start--md height-100 theme-light padding-2 gap-2"> <div class="width-30 width-auto--md"> <img class="border-radius box-shadow-1" src="/img/library/moduleImages/featured_image_222-23061209064736.jpeg" alt="Properties of Liquids"> </div> <div class="flex-grow-shrink"> <h2 class="h6 font-weight-normal"> Properties of Liquids: <em>Intermolecular forces, cohesion, adhesion, and viscosity</em> </h2> </div> </article> </a> </li> <li> <a class="no-hover-focus height-100" href="/en/library/Chemistry/1/Properties-of-Solids/209"> <article class="flex-row align-items-center flex-column--md align-items-start--md height-100 theme-light padding-2 gap-2"> <div class="width-30 width-auto--md"> <img class="border-radius box-shadow-1" src="/img/library/moduleImages/featured_image_209-23061209064721.jpeg" alt="Properties of Solids"> </div> <div class="flex-grow-shrink"> <h2 class="h6 font-weight-normal"> Properties of Solids: <em>The influence of crystal structure on behavior</em> </h2> </div> </article> </a> </li> <li> <a class="no-hover-focus height-100" href="/en/library/Chemistry/1/The-Mole/53"> <article class="flex-row align-items-center flex-column--md align-items-start--md height-100 theme-light padding-2 gap-2"> <div class="width-30 width-auto--md"> <img class="border-radius box-shadow-1" src="/img/library/moduleImages/featured_image_53-23061209064540.jpeg" alt="The Mole and Atomic Mass"> </div> <div class="flex-grow-shrink"> <h2 class="h6 font-weight-normal"> The Mole and Atomic Mass: <em>Definitions, conversions, and Avogadro's number</em> </h2> </div> </article> </a> </li> </ul> </div> </footer> </div>    </article> </div> </div> </main> <script id="ngssCommentdata" type="application/json"> [{"ngss_tag_id":null,"type":"dci","tag":"","name":null,"description":null,"comment":"<p>This selection develops the DCI element listed below. 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To understand the visible properties, forces within and between atoms must be considered.<\/p>\r\n\r\n<p><strong>PS1.A Matter and Its Interactions; HS-PS1.A Structure and Properties of Matter:<\/strong> The structure and interactions of matter at the bulk scale are determined by electrical forces within and between atoms.<\/p>","is_public":"1","mod_ngss_comment_id":"533","display_order":"4","dimension":"dci","dimension_full":"Disciplinary Core Ideas"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>Patterns observed at one scale may be linked to causality taking place at a different scale.<\/p>\r\n\r\n<p>HS-CC.1 Patterns: Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.<\/p>","is_public":"1","mod_ngss_comment_id":"534","display_order":"5","dimension":"cc","dimension_full":"Crosscutting Concepts"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>Structure-function can be used to explain observed properties of matter.<\/p>\r\n\r\n<p><strong>HS-CC.6 Structure and Function:<\/strong> The functions and properties of natural and designed objects and systems can be inferred from their overall structure, the way their components are shaped and used, and the molecular substructures of its various materials.<\/p>","is_public":"1","mod_ngss_comment_id":"535","display_order":"6","dimension":"cc","dimension_full":"Crosscutting Concepts"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>This CC element grounds the thinking about the link between energy and changes in matter.<\/p>\r\n\r\n<p><strong>HS-CC.5 Energy and Matter:<\/strong> Changes of energy and matter in a system can be described in terms of energy and matter flows into, out of, and within that system.<\/p>","is_public":"1","mod_ngss_comment_id":"536","display_order":"7","dimension":"cc","dimension_full":"Crosscutting Concepts"},{"ngss_tag_id":null,"type":"p","tag":"","name":null,"description":null,"comment":"<p>It is useful to calculate the number of moles in a sample when preparing solutions.<\/p>\r\n\r\n<p><strong>HS-SEP.5 Using Mathematical and Computational Thinking:<\/strong> Apply techniques of algebra and functions to represent and solve scientific and engineering problems.<\/p>","is_public":"1","mod_ngss_comment_id":"537","display_order":"8","dimension":"p","dimension_full":"Science and Engineering Practices"},{"ngss_tag_id":null,"type":"dci","tag":"","name":null,"description":null,"comment":"<p>This selection develops the DCI element listed below. To understand the visible properties, forces within and between atoms must be considered.<\/p>\r\n\r\n<p><strong>PS1.A Matter and Its Interactions; HS-PS1.A Structure and Properties of Matter:<\/strong> The structure and interactions of matter at the bulk scale are determined by electrical forces within and between atoms.<\/p>","is_public":"1","mod_ngss_comment_id":"538","display_order":"9","dimension":"dci","dimension_full":"Disciplinary Core Ideas"},{"ngss_tag_id":null,"type":"dci","tag":"","name":null,"description":null,"comment":"<p>This selection develops the DCI element listed below. To understand the visible properties, forces within and between atoms must be considered.<\/p>\r\n\r\n<p><strong>PS1.A Matter and Its Interactions; HS-PS1.A Structure and Properties of Matter:<\/strong> The structure and interactions of matter at the bulk scale are determined by electrical forces within and between atoms.<\/p>","is_public":"1","mod_ngss_comment_id":"539","display_order":"10","dimension":"dci","dimension_full":"Disciplinary Core Ideas"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>Observed patterns in solubility led to the construction of a set of solubility guidelines.<\/p>\r\n\r\n<p><strong>HS-CC.1 Patterns:<\/strong> Different patterns may be observed at each of the scales at which a system is studied and can provide evidence for causality in explanations of phenomena.<\/p>","is_public":"1","mod_ngss_comment_id":"540","display_order":"11","dimension":"cc","dimension_full":"Crosscutting Concepts"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>The solubility guidelines provide predictive support when combining substances.<\/p>\r\n\r\n<p><strong>HS-CC.2: Cause and Effect:<\/strong> Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.<\/p>","is_public":"1","mod_ngss_comment_id":"541","display_order":"12","dimension":"cc","dimension_full":"Crosscutting Concepts"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>Understanding what occurs at a sub-microscopic scale supports what is seen at a macroscopic scale.<\/p>\r\n\r\n<p><strong>HS-CC.2 Cause and Effect:<\/strong> Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.<\/p>","is_public":"1","mod_ngss_comment_id":"542","display_order":"13","dimension":"cc","dimension_full":"Crosscutting Concepts"},{"ngss_tag_id":null,"type":"p","tag":"","name":null,"description":null,"comment":"<p>Watson analyzed the data he collected outside in the winter to develop an understanding of freezing point depression.<\/p>\r\n\r\n<p><strong>HS-SEP.4 Analyzing and Interpreting Data:<\/strong> Analyze data using tools, technologies, and\/or models (e.g., computational, mathematical) in order to make valid and reliable scientific claims or determine an optimal design solution.<\/p>","is_public":"1","mod_ngss_comment_id":"543","display_order":"14","dimension":"p","dimension_full":"Science and Engineering Practices"},{"ngss_tag_id":null,"type":"p","tag":"","name":null,"description":null,"comment":"<p>Blagden's Law quantifies the presence of solute particles makes it harder for a solvent to coalesce and form a solid, and that forming a solid becomes harder in a way that's regular and predictable.<\/p>\r\n\r\n<p><strong>HS-SEP.5 Using Mathematical and Computational Thinking:<\/strong> Use mathematical, computational, and\/or algorithmic representations of phenomena or design solutions to describe and\/or support claims and\/or explanations.<\/p>","is_public":"1","mod_ngss_comment_id":"544","display_order":"15","dimension":"p","dimension_full":"Science and Engineering Practices"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>The molecular scale properties (ex. colligative properties) can explain what is observed at the macroscopic scale.<\/p>\r\n\r\n<p><strong>HS-CC.2 Cause and Effect:<\/strong> Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.<\/p>","is_public":"1","mod_ngss_comment_id":"545","display_order":"16","dimension":"cc","dimension_full":"Crosscutting Concepts"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>The molecular scale properties (ex. colligative properties) can explain what is observed at the macroscopic scale.<\/p>\r\n\r\n<p><strong>HS-CC.2 Cause and Effect:<\/strong> Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.<\/p>","is_public":"1","mod_ngss_comment_id":"546","display_order":"17","dimension":"cc","dimension_full":"Crosscutting Concepts"},{"ngss_tag_id":null,"type":"dci","tag":"","name":null,"description":null,"comment":"<p>This selection develops the DCI element listed below. To understand the chemical processes, consideration of the relationship between kinetic energy and the motion of the molecules.<\/p>\r\n\r\n<p><strong>PS1 Matter and Its Interactions; HS-PS1.B Chemical Reactions:<\/strong> Chemical processes, their rates, and whether or not energy is stored or released can be understood in terms of the collisions of molecules and the rearrangements of atoms into new molecules, with consequent changes in the sum of all bond energies in the set of molecules that are matched by changes in kinetic energy.<\/p>","is_public":"1","mod_ngss_comment_id":"547","display_order":"18","dimension":"dci","dimension_full":"Disciplinary Core Ideas"},{"ngss_tag_id":null,"type":"cc","tag":"","name":null,"description":null,"comment":"<p>The molecular scale properties (ex. colligative properties) can explain what is observed at the macroscopic scale.<\/p>\r\n\r\n<p><strong>HS-CC.2 Cause and Effect:<\/strong> Cause and effect relationships can be suggested and predicted for complex natural and human designed systems by examining what is known about smaller scale mechanisms within the system.<\/p>","is_public":"1","mod_ngss_comment_id":"548","display_order":"19","dimension":"cc","dimension_full":"Crosscutting Concepts"}]</script>   <footer class="position-relative box-shadow-1 font-size-md" id="global-footer"> <h2 class="screen-reader-only">Page Footer</h2> <div class="back-to-top"> <div class="container wide"> <button class="button button--has-icon font-size-sm"> <span class="icon icon-arrow-up"></span> <span class="button__text">Back to top</span> </button> </div> </div> <div class="container wide padding-y-2"> <div class="grid grid--column-2--md grid--column-4--lg gap-4 grid--divider--fill-x"> <nav> <ul class="nav font-weight-bold"> <li> <a href="/en/library" title="Readings & quizzes"> Library </a> </li> <li> <a href="/en/glossary" title="Science terms"> Glossary </a> </li> <li> <a href="/en/classroom" title="Courses & bookmarks"> Classroom </a> </li> </ul> </nav> <nav> <ul class="nav"> <li><a href="/en/about">About</a></li> <li><a href="/en/help">Contact</a></li> <li><a href="/en/about/jobs">Jobs</a></li> <li><a href="/en/help/faq">FAQ</a></li> </ul> </nav> <div> <ul class="nav nav--horizontal margin-bottom-2"> <li> <a class="display-flex" href="https://www.nsf.gov" target="_blank" rel="noopener"> <img src="/images/sponsor-nsf.png" width="60" height="60" alt="US Education Department Logo" /> </a> </li> <li> <a class="display-flex" href="https://www.ed.gov/" target="_blank" rel="noopener"> <img src="/images/sponsor-doe.png" width="60" height="60" alt="US Education Department Logo" /> </a> </li> </ul> <p>Visionlearning is supported by the The National Science Foundation and the U.S. Department of Education. 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