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href="./">Oxygen - <sub>8</sub>O</a>  <audio id="myAudio_f"> <source src="../_media/elements/snds_f/O.mp3" type="audio/mpeg">Your user agent does not support the HTML5 Audio element. </audio> <button class="pure-button p_button" style=" display: inline;" type="button" onclick="audf_play_pause()"> 🔊  </button> <script> function audf_play_pause() { var myAudiof = document.getElementById("myAudio_f"); if (myAudiof.paused) { myAudiof.play(); } else { myAudiof.pause(); }} </script></span> </div> </div> </div> <div id="main">  <div class="pure-u-1 pure-u-sm-1-1"> <div class="pure-menu pure-menu-horizontal pure-menu-scrollable"> <a href="#" class="pure-menu-link pure-menu-heading">▸▸</a> <ul class="pure-menu-list"> <li class="pure-menu-item">🇬🇧 Oxygen</li> <li class="pure-menu-item">🇺🇦 Кисень</li> <li class="pure-menu-item">🇨🇳 氧</li> <li class="pure-menu-item">🇳🇱 Zuurstof</li> <li class="pure-menu-item">🇫🇷 Oxygène</li> <li class="pure-menu-item">🇩🇪 Sauerstoff</li> <li class="pure-menu-item">🇮🇱 חמצן</li> <li class="pure-menu-item">🇮🇹 Ossigeno</li> <li class="pure-menu-item">🇯🇵 酸素</li> <li class="pure-menu-item">🇵🇹 Oxigênio</li> <li class="pure-menu-item">🇪🇸 Oxi´geno</li> <li class="pure-menu-item">🇸🇪 Syre</li> <li class="pure-menu-item">🇷🇺 Кислород</li> </ul> </div> </div> <div class="pure-g"> <div class="pure-u-1 pure-u-sm-1-1"> <div class="google_navbar_positioning"> <form action="https://www.google.com" id="cse-search-box"> <div> <input type="hidden" name="cx" value="partner-pub-9334432533380510:6223510783"> <input type="hidden" name="ie" value="UTF-8"> <input type="text" name="q" size="28"> <input type="submit" name="sa" value="Search"> </div> </form> <script> </script> </div> </div> </div> <main> <div class="pure-g"> <div class="pure-u-1 pure-u-sm-1-1"> <h1 class="p">Oxygen - <sub><small>8</small></sub>O: the essentials</h1> <div class="pure-menu pure-menu-horizontal pure-menu-scrollable"> <ul class="pure-menu-list z_menu"> <li class="pure-menu-item p"><a href="../oxygen/" class="pure-menu-link">▸▸ O Essentials</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/physics.html">Physical properties</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/atoms.html">Electron shell data</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/atom_sizes.html">Atom sizes</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/electronegativity.html">Electronegativity</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/isotopes.html" >Isotopes and NMR</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/crystal_structure.html">Crystal structure</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/thermochemistry.html">Thermochemistry</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/history.html">History</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/uses.html">Uses</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/geology.html">Geology</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/biology.html">Biology</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/compounds.html">Binary compounds</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/compound_properties.html" >Compound properties</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/chemistry.html">Element reactions</a></li> <li class="pure-menu-item p"><a class="pure-menu-link" href="../oxygen/contents.html">List all O properties</a></li> </ul> </div> </div> </div>  <div class="pure-g"> <div class="pure-u-1 pure-u-sm-1-2">  <ul class="ul_facts_table"> <li><a href="../periodicity/name_english/" title="Element names">Name</a>: oxygen</li> <li><a href="../periodicity/name_english/" title="Element symbol">Symbol</a>: O</li> <li><a href="../periodicity/atomic_number/" title="Element atomic number">Atomic number</a>: 8 </li> <li><a href="../periodicity/atomic_weight/" title="Element atomic weight">Relative atomic mass (<i>A</i><sub>r</sub>)</a>: 15.999 range: [15.99903, 15.99977] [see notes <a href="../periodicity/atomic_weight/index.html#footnote_g">g</a> <a href="../periodicity/atomic_weight/index.html#footnote_r">r</a>] </li> <li><a href="../periodicity/standard_state/" title="Element standard state">Standard state</a>: gas at 298 K</li> <li><a href="../periodicity/standard_state/" title="Element colour">Appearance</a>: colourless as a gas, liquid is pale blue</li> <li><a href="../periodicity/classification/" title="Classification of oxygen as metal, non-metal, or semi-metal">Classification</a>: Non-metallic </li> </ul> </div> <div class="pure-u-1 pure-u-sm-1-2"> <ul class="ul_facts_table"> <li><a href="../periodicity/group_number/" title="The group within which oxygen is located">Group in periodic table</a>: 16</li> <li><a href="../periodicity/group_number/" title="The name of the group (if there is one) within which oxygen is located">Group name</a>: Chalcogen</li> <li><a href="../periodicity/group_number/" title="The period within which oxygen is located">Period in periodic table</a>: 2</li> <li><a href="../periodicity/group_number/" title="The block within which oxygen is located">Block in periodic table</a>: p</li> <li><a href="../periodicity/electron_shell_structure/" title="Shell structure">Shell structure</a>: 2.6 </li> <li><a href="../periodicity/cas_registry_id/" title="Chemical Abstract Service (CAS) Registry numbers for the elements">CAS Registry</a>: 7782-44-7</li> </ul> </div> </div> <p class="p_first"> Oxygen atoms have 8 electrons and the <strong><a href="../periodicity/electron_shell_structure/">shell structure</a></strong> is 2.6. The <strong> <a href="../periodicity/electronic_configuration/">ground state electronic configuration of neutral oxygen is</a></strong> [<strong>He</strong>].<strong>2s</strong><sup>2</sup>.<strong>2p</strong><sup>4</sup> and the <strong><a href="../periodicity/term_symbol/">term symbol of oxygen </a> is</strong> <sup>3</sup><strong>P</strong><sub>2</sub>. </p> <h2 class="p">Oxygen: description  <audio id="myAudio_desc"> <source src="../_media/elements/snds_description/O.mp3" type="audio/mpeg">Your user agent does not support the HTML5 Audio element. </audio> <button class="pure-button p_button" style="display: inline;" type="button" onclick="auddesc_play_pause()">🔊</button> <script> function auddesc_play_pause() { var myAudiodesc = document.getElementById("myAudio_desc"); if (myAudiodesc.paused) { myAudiodesc.play(); } else { myAudiodesc.pause(); }} </script> </h2> <div class="pure-g"> <div class="pure-u-1 pure-u-sm-1-1"> <p class="p_first">Oxygen is a Group 16 element. While about one fifth of the atmosphere is oxygen gas, the atmosphere of Mars contains only about 0.15% oxygen. Oxygen is the third most abundant element found in the sun, and it plays a part in the carbon-nitrogen cycle, one process responsible for stellar energy production. Oxygen in excited states is responsible for the bright red and yellow-green colours of the aurora. About two thirds of the human body, and nine tenths of water, is oxygen. The gas is colourless, odourless, and tasteless. Liquid and solid oxygen are pale blue (see picture above) and strongly paramagnetic (contains unpaired electrons).</p> <p class="p_first">Ozone (O<sub>3</sub>) is the second allotrope of oxygen. It is formed from electrical discharges or ultraviolet light acting on O<sub>2</sub>. It is an important component of the atmosphere (in total amounting to the equivalent of a layer about 3 mm thick at ordinary pressures and temperatures) which is vital in preventing harmful ultraviolet rays of the sun from reaching the earth's surface. Aerosols in the atmosphere have a detrimental effect on the ozone layer. Large holes in the ozone layer are forming over the polar regions and these are increasing in size annually. Paradoxically, ozone is toxic! Undiluted ozone is bluish in colour. Liquid ozone is bluish-black, and solid ozone is violet-black.</p> <p>Oxygen is very reactive and oxides of most elements are known. It is essential for respiration of all plants and animals and for most types of combustion.</p> <p>Oxygen occurs as two allotropes, dioxygen and trioxygen (ozone). Dioxygen, O<sub>2</sub>, is a diatomic colourless oxidizing gas but a pale blue liquid upon condensation. It is paramagnetic (that is, possesses unpaired electrons) as a result of two unpaired electrons in the two O<sub>2</sub> π* orbitals. It makes up about a fifth of the earth's atmosphere.</p> <p>Ozone, O<sub>3</sub>, is a very reactive blue gas characterized by a pungent "electrical" smell (the name ozone derives from the Greek <em>ozein</em>, to smell). Ozone molecules are bent with a bond angle of about 117° in the gas phase. Ozone condenses to a blue-black liquid (boiling point -111.9°C and further cooling results in a dark violet-black solid (melting point -192.5°C. </p> <p>Ozone is unstable thermodynamcally with respect to dioxygen but only converts to O<sub>2</sub> slowly in the absence of a catalyst. </p> <p class="equation">2O<sub>3</sub>(g) → 3O<sub>2</sub>(g)</p> <p class="pure-img"><img src="../_media/elements/allotropes/O/ozone.png" alt="ozone crystal structure" /><br />Arrangements of ozone molecules, O<sub>3</sub>, in the solid state.</p> <p>Ozone is present in the atmosphere as well, but at amuch lower level than O<sub>2</sub>. Ozone is a key component of the upper atmosphere because it has the ability to absorb ultraviolet light in the 220-290 nm range, so preventing harmful rays at those wavelengths reaching the earth's surface. These days, various factors deplete the ozone layer in the upper atmosphere and the "ozone holes" in the northern and southern polar regions are of particular concern.</p> </div> </div>  <div class="pure-g display_table"> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: physical properties</h2> <ul class="spark_table_list"> <li><a href="../periodicity/density/" title="view definition and images showing periodicity for density of elemental solids"><img alt="Density of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Density of solid</a>: 1495 kg m<sup>-3</sup></li> <li><a href="../periodicity/molar_volume/" title="view definition and images showing periodicity for molar volumes of the elements"><img alt="Molar volume of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Molar volume</a>: 17.36 cm<sup>3</sup></li> <li><a href="../periodicity/thermal_conduct/" title="show definition and view pictures showing periodicity of thermal conductivity in the periodic table"><img alt="Thermal conductivity of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Thermal conductivity</a>: 0.02658 W m<sup>‑1</sup> K<sup>‑1</sup></li> </ul> <p><a class="pure-button" href="./physics.html">More physical properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: heat properties</h2> <ul class="spark_table_list"> <li><a href="../periodicity/melting_point/" title="show definition and view pictures showing periodicity of melting point in the periodic table"><img alt="Melting point on a miniature periodic table spark table" src="data:image/png;base64,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" /> Melting point</a>: 54.8 [‑218.3 °C (‑360.9 °F)] K</li> <li><a href="../periodicity/boiling_point/" title="show definition and view pictures showing periodicity of boiling point in the periodic table"><img alt="Boiling point on a miniature periodic table spark table" src="data:image/png;base64,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" /> Boiling point</a>: 90.2 [‑182.9 °C (‑297.2 °F)] K</li> <li><a href="../periodicity/enthalpy_fusion/" title="show definition and view pictures showing periodicity of fusion enthalpy in the periodic table"><img alt="Enthalpy of fusion on a miniature periodic table spark table" src="data:image/png;base64,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" /> Enthalpy of fusion</a>: 20.5 kJ mol<sup>-1</sup></li> </ul> <p><a class="pure-button" href="./thermochemistry.html">More thermochemical properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: atom sizes</h2> <ul class="spark_table_list"> <li><a href="../periodicity/atom_radius_emp/" title="View atomic radius data for the elements"><img alt="Atomic radius (empirical) of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,iVBORw0KGgoAAAANSUhEUgAAAFAAAAAwCAIAAAF+gFo2AAAABGdBTUEAANkDQtZPoQAAAAlwSFlzAAALEwAACxMBAJqcGAAAACR0RVh0U29mdHdhcmUAUXVpY2tUaW1lIDcuNS41IChNYWMgT1MgWCkADDxZHwAAAAd0SU1FB9kBEhYYEc6VNooAAAOhSURBVHic7Zo9TutAEIDHKIAUQEABBUhcgBNQIl64AukoaJGokBASqek5ARIFHQeIlQYqmjQBySAhGijSAA0SUJjZnbUz9npjGyfxA/srTLze//nxzhiAWNzz83BJu+06TrPZtMTN1hasrqon4+PiOj0N1aq9sjImbhwHXl7EAyxF3t7g6gouLuLHtdRg2L/s1t7e9p/VarXYaR8dhUtaLbfTcZ+eROcuznl9HZaX4etLTXtyEmZnxbOdnTG4uYHXV3h/V8+QVgvabVxVspm7m5swPx+aeW/aruvG9xME9xuvFfGzXncPDqzj4z613ZMTmJuDqSm6teVVNr68hG5X7OrSkpJJtSrW/vEhtqLbFXN+eFCPaPVra6qxfXr6b3/fPjxMO3mrNzHcGG9WPSYmehvttzk7SzvMMPixqKT6Nxq6/YQHQL1Ei0LVdBzSTlCiursTIukPKiqTM8zMeI07HdH37i4sLoq99Tvi+4yFqOWfn1pjNFnUBKptUhKAgJJIy5Brfn5WJk9gSx8sRJPDju7vxeqw2vW1LdVLjWw3m0LDmK1HsLERsylpyaSelXBVCGxy9Fr+D93OiCsZ9ihNCf329rrRAO/NZNXrP+4aTU/8QUcNnsyYYtu3t35Nb2BUWoB4q4wFzRZBy0V0fZOGGBxYmrOaNRo1gnbtz1efkKavCqqJVo/4ht9vYLRRhLwB75psnyATR7NG0EX4w/g+xIe34uXsveoNjG4EvFWi0wjBvQqHOqX6eNgAb+dokxcWxPXxES/23l6oqRrYlsqGXghMxpuQgbupgWPpRcIBQpRO6miuzjiM5u0qkfV6nRKGrlMI5U+42d/N6F8SY8MezERub6fcVzzy12LuKx75+zj3FY/8IJD7ikd+Asl7xaM/+uS24uKR22Evb62OYMinzFKrS0oGRMBv8VDCsiJc2i/CD1gg+EWjcN4j6Kdl9ETw3HmWSCoLKgojKBYj+HvDcLLlMRqn4BKmaJHIHjNmh6JOgmJPIsm5iEVonIJLmEXHHBUpExRXEaGPUrEkOIcG4H1SrE3oEbdOKWEiKGHKBhA8J8AxxfscHkVT3oCg7AHBpafnH3RMY5nqGz7qF1zClP0guK3qmRAdU27EBJcM75/yJwT3KdwzU0aFkHkVQs+u6BRbwjY7f1LOR5VnyfxkYQgfzAon4ZK/TqKgV2X2iCTn2CQkyJqlJck/eRXOhs15SxNcMpyUUhqK5y8lXFI8vgEaOGdEgPG38AAAAABJRU5ErkJggg==" /> Atomic radius (empirical)</a>: 60 pm</li> <li><a href="../periodicity/rad_cov_single/" title="View molecular single bond covalent radii data for the elements"><img alt="Covalent (single bond) radius on a periodic table spark table" src="data:image/png;base64,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" /> Molecular single bond covalent radius</a>: 63 (coordination number 2) ppm</li> <li><a href="../periodicity/van_der_waals_rad/" title="View van der Waals' radius data for the elements"><img alt="van der Waals radius on a periodic table spark table" src="data:image/png;base64,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" /> van der Waals radius</a>: 150 ppm</li> </ul> <p><a class="pure-button" href="./atom_sizes.html">More atomc size properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: electronegativities</h2> <ul class="spark_table_list"> <li><a href="../periodicity/eneg_pauling/" title="View definition and pictures showing periodicity of Pauling electronegativity"><img alt="Pauling electronegativity of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Pauling electronegativity</a>: 3.44 (Pauling units)</li> <li><a href="../periodicity/eneg_allred_rochow/" title="View definition and pictures showing periodicity of Allred Rochow electronegativity"><img alt="Allred-Rochow electronegativity of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" />Allred Rochow electronegativity</a>: 3.50 (Pauling units)</li> <li><a href="../periodicity/eneg_mulliken_j/" title="View definition and pictures showing periodicity of Mulliken-Jaffe electronegativity"><img alt="Mulliken-Jaffe electronegativity of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" />Mulliken-Jaffe electronegativity</a>: 3.41 (16.7% s orbital)</li> </ul> <p><a class="pure-button" href="./electronegativity.html">More electronegativity properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: orbital properties</h2> <ul class="spark_table_list"> <li><a href="../periodicity/ionis_energy_1/" title="View definition and pictures showing first ionisation energies"><img alt="First ionization energy the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> First ionisation energy</a>: 1313.94 kJ mol<sup>‑1</sup></li> <li><a href="../periodicity/ionis_energy_2/" title="View definition and pictures showing second ionisation energies"><img alt="Second ionization energy the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Second ionisation energy</a>: 3388.67 kJ mol<sup>‑1</sup></li> <li><a href="../periodicity/ionis_energy_3/" title="View definition and pictures showing third ionisation energies"><img alt="Third ionization energy the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Third ionisation energy</a>: 5300.47 kJ mol<sup>‑1</sup></li> </ul> <p><a class="pure-button" href="./atoms.html">More orbital properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: abundances</h2> <ul class="spark_table_list"> <li><a href="../periodicity/abund_universe/" title="Definitions and pictures showing periodicity of element abundances in the universe"><img alt="Chemical elements abundance by weight in the universe on a miniature periodic table spark table" src="data:image/png;base64,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" />Universe</a>: 10000000 ppb by weight</li> <li><a href="../periodicity/abund_crust/" title="Definitions and pictures showing periodicity of element abundances in the earth's crust"><img alt="Chemical elements abundance by weight in the earth's crust on a miniature periodic table spark table" src="data:image/png;base64,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" />Crustal rocks</a>: 460000000 ppb by weight</li> <li><a href="../periodicity/abund_humans/" title="Abundance in humans of the chemical elements displayed graphically"><img alt="Chemical elements abundance by weight in humans on a miniature periodic table spark table" src="data:image/png;base64,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" />Human</a>: 610000000 ppb by weight</li> </ul> <p><a class="pure-button" href="./geology.html">More geological data...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: crystal structure</h2> <figure><img class="pure-img" src="../_media/elements/crystal_structure_image/O-sf.jpg" alt="O crystal structure"><figcaption>The solid state structure of oxygen is: monoclinic.</figcaption></figure> <p><a class="pure-button" href="./crystal_structure.html">More crystallographic data...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: biological data</h2> <ul class="spark_table_list"> <li><a href="../periodicity/abund_humans/" title="View definition and pictures showing human abundance by weight"><img alt="Human abundance by weight of the chemical elements on a miniature periodic table spark table" src="data:image/png;base64,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" /> Human abundance by weight</a>: 610000000 ppb by weight</li> </ul> <p class="p_first">Oxygen atoms are present in water (H<sub>2</sub>O) and water is essential to all life. Oxygen and is present in many organic compounds. Most organisms use oxygen for respiration. While oxygen (O<sub>2</sub>) is necessary for life, oxygen as ozone (O<sub>3</sub>) is highly toxic. On the other hand, ozone is an important component of the atmosphere (the ozone layer) and helps to shield us from harmful ultraviolet rays from the sun. </p> <p><a class="pure-button" href="./biology.html">More biological data...</a></p> <div> <script async src="//pagead2.googlesyndication.com/pagead/js/adsbygoogle.js"></script>  <ins class="adsbygoogle" style="display:inline-block;width:300px;height:250px" data-ad-client="ca-pub-9334432533380510" data-ad-slot="2897369985"></ins> <script> (adsbygoogle = window.adsbygoogle || []).push({}); </script> </div> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: uses</h2> <p><a class="pure-button" href="./uses.html">Uses...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: reactions</h2> <p> Reactions of oxygen as the element with air, water, halogens, acids, and bases where known. </p> <p><a class="pure-button" href="./chemistry.html">View reactions of oxygen...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: binary compounds</h2> <p> Binary compounds with halogens (known as halides), oxygen (known as oxides), hydrogen (known as hydrides), and other compounds of oxygen where known. </p> <p><a class="pure-button" href="./compounds.html">View binary compounds...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: compound properties</h2> <p> Bond strengths; lattice energies of oxygen halides, hydrides, oxides (where known); and reduction potentials where known. </p> <p><a class="pure-button" href="./compound_properties.html">View compound properties...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: history</h2> <strong>Oxygen</strong> was <a href="../periodicity/discovery/" title="Further information on element discoveries">discovered</a> by Joseph Priestley, Carl Scheele in 1774 at England and Sweden. <a href="../periodicity/discovery/" title="Further information on element discoveries">Origin of name</a>: from the Greek words "<em>oxy genes</em>" meaning "<em>acid</em>" (sharp) and "<em>forming</em>" (acid former). <p><a class="pure-button" href="./history.html">More history...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-2"> <h2 class="p">Oxygen: isotopes</h2> <div><figure><img class="pure-img" src="../_media/elements/isotopes/isotope_abundance_O.png" alt="Isotope abundances of oxygen" /><figcaption>Isotope abundances of oxygen with the most intense signal set to 100%.</figcaption></figure></div> <p class="p_first">All three Oxygen isotopes have medical applications. O-16 is used in the production of radioactive N-13 which is used for PET imaging and myocardial perfusion. O-17 can be used as a tracer in the study of cerebral oxygen utilization. Large quantities of O-18 are used for the production of F-18. F-18 is used to produce 2-[<sup>18</sup>F]fluoro-2-deoxyglucose (FDG) which is used as a tracer in positron emission tomography or PET. Millions of these FDG-PET medical procedures are performed annually to investigate a range of diseases in various human organs. </p> <p><a class="pure-button" href="./isotopes.html">More isotope and NMR data...</a></p> </div> <div class="pure-u-1 pure-u-md-1-1 pure-u-lg-1-1"> <h2 class="p">Oxygen: isolation</h2> <p class="p_first"> <a href="../periodicity/isolation/" title="literature sources referring to isolation of pure oxygen">Isolation</a>: there is not normally any need ot make oxygen in the laboratory as it is readily available commercially or through in-house air liquefaction plants. However the decomposition of potassium chlorate is one route to O<sub>2</sub> and decomposition of potassium permanganate is another. In addition, electrolysis of KOH using nickel electrodes gives clean oxygen.</p> <p class="equation">2KClO<sub>3</sub> (400°C) → 2KCl + 3O<sub>2</sub></p> <p class="equation">2KMnO<sub>4</sub> (214°C) → K<sub>2</sub>MnO<sub>4</sub> + MnO<sub>2</sub> + O<sub>2</sub></p> <p>Ozone (O<sub>3</sub>), the other allotrope of oxygen, is made by silent electric discharge through oxygen flowing through a cooled system. This can give up to a10% proportion of ozone and the ozone is purified by fractional liquefaction (with care!).</p> </div> </div>  </main> <div id="footer"> <footer> <div class="footer"> <div class="pure-g"> <div class="pure-u-1-2 pure-u-sm-1-2 pure-u-lg-1-4 pure-menu custom-restricted-width"> <ul class="pure-menu-list"> <li class="pure-menu-heading footer_h">Key properties</li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/periodicity/eneg_pauling/">Electronegativity </a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/periodicity/melting_point/">Melting point</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/periodicity/density/">Density </a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/periodicity/molar_volume/">Molar volume</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/periodicity/ionis_energy_1/">Ionization energy (1st)</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/periodicity/covalent_radius/">Covalent radius</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/periodicity/metallic_radius/">Metallic radius</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/periodicity/abund_crust/">Abundance: earth's crust</a></li> </ul> </div> <div class="pure-u-1-2 pure-u-sm-1-2 pure-u-lg-1-4 pure-menu custom-restricted-width"> <ul class="pure-menu-list"> <li class="pure-menu-heading footer_h">Shop</li> <li class="pure-menu-item">Sorry, shop closed</li> </ul> </div> <div class="pure-u-1-2 pure-u-sm-1-2 pure-u-lg-1-4 pure-menu custom-restricted-width"> <ul class="pure-menu-list"> <li class="pure-menu-heading footer_h">Social</li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.facebook.com/webelements.periodic.table">Facebook</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://twitter.com/periodic_table">Twitter</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.pinterest.com/periodictable/">Pinterest</a></li> </ul> </div> <div class="pure-u-1-2 pure-u-sm-1-2 pure-u-lg-1-4 pure-menu custom-restricted-width"> <ul class="pure-menu-list"> <li class="pure-menu-heading footer_h">Administration</li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/nexus/your-privacy/" title="Your privacy">Privacy</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/nexus/about-webelements/" title="About WebElements">About</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/nexus/webelements-and-copyright/" title="Copyright information about WebElements">Copyright</a></li> <li class="pure-menu-item"><a class="pure-menu-link" href="https://www.webelements.com/nexus/acknowledgements/" title="Acknowledgements">Thanks...</a></li> </ul> </div> </div> </div> <address> <p> <a href="https://www.webelements.com/"><img class="logo_m" src="../_media/icons/logo_60.png" alt="WebElements home" /></a><br /> <strong>WebElements:</strong> THE periodic table on the WWW [<a href="https://www.webelements.com/">www.webelements.com</a>]<br /> <a href="https://www.webelements.com/nexus/webelements-and-copyright/">Copyright </a> 1993-2025 <a href="https://winter.group.shef.ac.uk/">Mark Winter</a> [ <a href="https://www.sheffield.ac.uk/chemistry/">The University of Sheffield </a> and WebElements Ltd, UK]. 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