CINXE.COM
isotope (chemistry) | Britannica
<!doctype html> <html lang="en" class="topicmediabrowse-desktop ui-ie7 ui-ie"> <head prefix="og: https://ogp.me/ns# fb: https://ogp.me/ns/fb#"> <meta charset="utf-8"> <meta http-equiv="Content-Type" content="text/html; charset=UTF-8" /> <meta name="viewport" content="width=device-width, initial-scale=1.0" /> <link rel="dns-prefetch" href="https://cdn.britannica.com/mendel-resources/3-130"> <link rel="preconnect" href="https://cdn.britannica.com/mendel-resources/3-130"> <link rel="preload" as="script" href="https://www.googletagservices.com/tag/js/gpt.js" /> <link rel="icon" href="/favicon.png" /> <meta name="description" content="Videos and Images for isotope (chemistry)" /> <meta name="keywords" content="britannica, reference, online, encyclopedia, encyclopaedia, store, dictionary, thesaurus" /> <link rel="canonical" href="https://www.britannica.com/science/isotope/images-videos" /> <meta name="robots" content="noindex,follow" /><title>isotope (chemistry) | Britannica</title> <script type="text/javascript" data-type="Init Mendel"> window.$UI = {}; window.Constants = {"LICENSE_URL": "/bps/license","DEFAULT_TEST_VERSION": "A","DEFAULT_STATE": "XX","QUIZ_URL": "/quiz","SPOTLIGHT_BROWSE_URL": "/stories/spotlight","CONTENT_TYPE_TEXT": "text/plain;charset=UTF-8","TOPIC_FACTS_DATA_URL": "/facts","QUIZ_BROWSE_IMAGE_QUIZZES": "images","TOPIC_MEDIA_PATH": "/images-videos","USER_PROFILE_URL": "/user","DEBUG_URL": "/debug","ONE_GOOD_FACT_URL": "/one-good-fact","ERROR_404_URL": "/error404","PROCON_CITED_IN_THE_NEWS_URL": "/procon/ProCon-in-the-News","PROCON_URL": "/procon","TOPIC_PAGE_CONTENT_AJAX_URL": "/topic-content/page","INFINITE_SCROLL_PREFIX_URL": "/scroll","TOPIC_TOP_QUESTION_BROWSE_URL": "/questions","CC_USD": "USD","domain": "britannica.com","SURVEY_URL": "/survey","CATEGORY_BROWSE_URL": "/browse","STORY_BROWSE_URL": "/stories","COUNTRY_US": "US","OPEN_MEDIA_OVERLAY_PARAMETER": "/media","NEWSLETTER_SUBSCRIPTION_URL": "/newsletter-subscription","MAINTENANCE_ERROR_URL": "https://maintenance.eb.com","IMARS_EDITOR_ID": "12365882","PROFILE_EB_EDITOR_URL": "/editor","WEB_INF_RESOURCES_PATH": "WEB-INF/resources","AI_ABOUT_PAGE_URL": "/about-britannica-ai","TOPIC_ADDITIONAL_INFO_PATH": "/additional-info","SUDOKU_GAME_URL": "/games/sudoku","CC_INR": "INR","ARTICLE_PRINT_URL": "/print/article","FIRST_EDITION_URL": "/subscriber/firstedition","WW1_PORTAL_URL": "/discover/World-War-I","MENDEL_COOKIE": "__mendel","DEMYSTIFIED_BROWSE_URL": "/stories/demystified","LIST_BROWSE_URL": "/list/browse","PROFILE_EXPERT_URL": "/contributor","ASSEMBLY_IMAGE_URL": "/image/assembly","DAY_IN_HISTORY_URL": "/on-this-day","DEFAULT_CURRENCY": "USD","CONTENT_TYPE_XML": "text/xml;charset=UTF-8","PORTAL_FINANCE_BROWSE_URL_PREFIX": "/money/browse","MONEY_IMARS_CATEGORY": "13000","AJAX_PREFIX_URL": "/ajax","TOPIC_BROWSE_URL": "/topic-browse","MARKETING_CONTENT": "/marketing-content","ENV_RUNTIME": "runtime","GALLERY_URL": "/gallery","topicUrlClassesList": "topic|animal|art|biography|event|place|plant|science|sports|technology|procon","CONTENT_TYPE_HTML": "text/html;charset=UTF-8","ENV_LOCAL": "override","MEDIA_OVERLAY_URL": "/media-overlay","CHATBOT_PAGE_URL": "/chatbot","NEWSLETTER_PAGE_URL": "/newsletters","ENV_DEV": "development","MEDIA_URL": "/media","TOPIC_TOP_QUESTION_URL": "/question","PORTAL_FINANCE_URL_PREFIX": "/money","PODCASTS_URL": "/podcasts","STAND_ALONE_VIDEO_URL": "/video","MORE_ON_THIS_DAY_URL": "/more-on-this-day","TOPIC_QUOTES_URL": "/quotes","SEARCH_PAGE_URL": "/search","PROCON_CLASS": "PROCON","KUSTOM_MENDEL_APPLICATION_ID": "1","TOPIC_CONTENT_AJAX_URL": "/topic-content/topic","ENV_BRANCH": "branch","ERROR_URL": "/error","MAIN_VERSION": "mainVersion","DEFAULT_S3_REGION": "US_EAST_1","TOPIC_COLLECTION_URL": "/summary","LOGINBOX_URL": "/auth/loginbox","ONE_GOOD_FACT_BROWSE_URL": "/one-good-fact/all-good-facts","QUIZ_BROWSE_URL": "/quiz/browse","BIO_BROWSE_URL": "/browse/biographies","LIST_URL": "/list","TIGHTROPE_QUIZ_URL": "/quiz/tightrope","ALPHA_BROWSE_URL": "/sitemap","CONTENT_TYPE_JSON": "application/json","DICTIONARY_URL": "/dictionary","COBRAND_IMAGE_URL": "/image/cobrand","PROCON_IN_THE_NEWS_URL": "/procon/pro-and-con-issues-in-the-news","PROCON_BROWSE_URL": "/procon","QUIZ_BROWSE_VOCAB_QUIZZES": "vocabulary-quizzes","SUBMISSION_URL": "/submission","EB_LOG_OUT": "/auth2/logout","ENV_PRODUCTION": "production","EXPLORE_PORTAL_URL": "/explore","TOPIC_AJAX_URL": "/ajax/topic","TOPIC_SUMMARY_BROWSE_URL": "/summaries","WTFACT_BROWSE_URL": "/stories/wtfact","VIDEO_CHANNEL_URL": "/videos","GALLERY_BROWSE_URL": "/gallery/browse","CACHE_URL": "/cache","PROCON_ABOUT_URL": "/procon/About-ProCon","COMPANION_BROWSE_URL": "/stories/companion","MEDIA_FOLDER": "/eb-media","SHOW_ALL_CONTRIBUTORS": "/additional-info#contributors","BRITANNICA_EDITORS_ID": "4419","ENV_CACHE_DISABLED": "mendelCache","CALCULATORS_BROWSE_URL": "/calculators","STORY_URL": "/story","DEFAULT_COUNTRY": "US","NAVBAR_URL": "/ajax/navbar","EB_LOGIN_URL": "/auth/eb-login","NEW_ARTICLES_URL": "/new-articles",}; window.CDN = "https://cdn.britannica.com"; window.CAM_LOGIN_URL = "https://cam.britannica.com"; window.CAM_SIGN_UP_URL = "https://cam.britannica.com/registration" window.Mendel = { "config" : { "domain": "britannica.com", "page": "TopicMediaBrowse", "videoPlayerId": "UyMCoK2v", "sharedUrl": "https://www.britannica.com/science/isotope/images-videos", "amuselabsUrl": "https://cdn3.amuselabs.com", "resourcesPrefixUrl": "https://cdn.britannica.com/mendel-resources/3-130/[url]?v=3.130.14", "date": 20241127, "userInfo": { "type": "ANONYMOUS" ,"currency": "AUUS" ,"country": "SG" ,"state": "XX" ,"timezone": "Asia/Singapore" ,"bcomId": "-622480390841427209" ,"hasAds": true ,"testVersion": "A" ,"adsTestVersion": "A" ,"consumerId": "" ,"instId": "" ,"consumerUserName": "" ,"instUserName": "" ,"cognito": null }, "tvs":{ "r":[25,25,25,25], "a": [25,25,25,25]}, "isLoggedInAsUser": false, "isPhone": false, "isDesktop": true, "logoutUrl": "/auth2/logout", "selfServiceUrl": "https://myaccount.britannica.com", "cdnUrl": "https://cdn.britannica.com", "chatbotApi": "https://www.britannica.com/chat-api", "fetchOffset": 800, "mendelCookieName": "__mendel", "mendelCookie": {"surveyShown":false,"visitedTopicId":0,"currentDate":20241127}, "autocompleteToSearchPage": false,"topicId": 296583 }, "GA": {"leg":"A","adLeg":"A","userType":"ANONYMOUS","pageType":"TopicMediaBrowse","gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false} }; </script> <meta property="fb:app_id" content="1887621861548296"/ <meta name="twitter:card" content="summary_large_image" /> <meta name="twitter:site" content="@britannica" /> <meta name="twitter:image" content="https://cdn.britannica.com/64/216564-138-51A467D7/What-are-isotopes.jpg" /> <meta name="twitter:description" content="Videos and Images for isotope (chemistry)"/> <meta property="og:type" content="ARTICLE"/> <meta property="og:title" content="isotope (chemistry) | Britannica"/> <meta property="og:description" content="Videos and Images for isotope (chemistry)"/> <meta property="og:site_name" content="Encyclopedia Britannica" /> <meta property="og:url" content="https://www.britannica.com/science/isotope/images-videos"/> <meta property="og:image" content="https://cdn.britannica.com/64/216564-138-51A467D7/What-are-isotopes.jpg" /> <meta property="og:image:type" content="image/jpeg" /> <script type="text/javascript" data-type="init opengraph"> Mendel.openGraph = {"type":"ARTICLE","title":"isotope (chemistry)","description":"Videos and Images for isotope (chemistry)","imageUrl":"https://cdn.britannica.com/64/216564-138-51A467D7/What-are-isotopes.jpg","imageType":"image/jpeg","pageUrl":"https://www.britannica.com/science/isotope/images-videos"}</script> <link rel="preconnect" href="https://fonts.googleapis.com/"> <link rel="dns-prefetch" href="https://fonts.googleapis.com/" > <link rel="stylesheet" href="https://fonts.googleapis.com/icon?family=Material+Icons"> <link href="https://cdn.britannica.com/mendel-resources/3-130/dist/vendor-bundle.css?v=3.130.14" rel="stylesheet" /> <link href="https://cdn.britannica.com/mendel-resources/3-130/dist/mendel-css.css?v=3.130.14" rel="stylesheet" /> <link href="https://cdn.britannica.com/mendel-resources/3-130/dist/topic-media-browse-page.css?v=3.130.14" rel="stylesheet" /> <script type="text/javascript"> if (self !== top) { top.location = self.location; } // if ('scrollRestoration' in history) { history.scrollRestoration = 'manual'; } </script> <script src="https://cdn.britannica.com/mendel-resources/3-130/js/at.js?v=3.130.14" async ></script> <script> dataLayer = []; </script> <script type="text/javascript">(function(w,d,s,l,i){w[l]=w[l]||[];w[l].push({'gtm.start': new Date().getTime(),event:'gtm.js'});var f=d.getElementsByTagName(s)[0], j=d.createElement(s),dl=l!='dataLayer'?'&l='+l:'';j.async=true;j.src= '//www.googletagmanager.com/gtm.js?id='+i+dl;f.parentNode.insertBefore(j,f); })(window,document,'script','dataLayer','GTM-5W6NC8'); </script> </head> <body data-leg="A" class="topic-media-browse-page user-ANONYMOUS user-ads md-desktop leg-ab-ie"> <!--- assertive yield ---> <script>Mendel.config.adProvider='ay';</script> <script async src="https://securepubads.g.doubleclick.net/tag/js/gpt.js"></script> <script> window.googletag = window.googletag || {cmd: []}; googletag.cmd.push(function() { googletag.defineSlot('/15510053/CMP_1x1', [1, 1], 'div-gpt-ad-1709766812090-0').addService(googletag.pubads()); googletag.pubads().enableSingleRequest(); googletag.enableServices(); }); </script> <script async defer src="https://launchpad-wrapper.privacymanager.io/0ccc6fe8-1870-4ad8-b47b-6d029ac116fc/launchpad-liveramp.js"></script> <script async src="https://JRyhoywLYXNLYMAhs.ay.delivery/manager/JRyhoywLYXNLYMAhs" type="text/javascript" referrerpolicy="no-referrer-when-downgrade" ></script><div class="ie-warning d-flex align-items-center align-self-center justify-content-center site-alert bg-orange"> <div> You are using an <strong>outdated</strong> browser. Please <a class="text-white text-underscore" href="https://browsehappy.com/">upgrade your browser</a> to improve your experience and security. </div> </div> <script id="json-navbar-info" type="application/json"> {"topSectionLinks":[{"title":"Ask the Chatbot","url":"/chatbot","navbarId":"CHATBOT"},{"title":"Games & Quizzes","url":"/quiz/browse","navbarId":"QUIZZES"},{"title":"ProCon","url":"/procon","navbarId":"PROCON"},{"title":"History & Society","url":"/History-Society","navbarId":"HISTORY"},{"title":"Science & Tech","url":"/Science-Tech","selected":true,"navbarId":"SCIENCE"},{"title":"Biographies","url":"/Biographies","navbarId":"BIOS"},{"title":"Animals & Nature","url":"/Animals-Nature","navbarId":"ANIMALS"},{"title":"Geography & Travel","url":"/Geography-Travel","navbarId":"GEOGRAPHY"},{"title":"Arts & Culture","url":"/Arts-Culture","navbarId":"ART"},{"title":"Money","url":"/money","navbarId":"MONEY"},{"title":"Videos","url":"/videos","navbarId":"VIDEOS"}],"selectedSuperCategory":{"id":6,"title":"Science & Tech","url":"Science-Tech","description":"Explore science and technology; astronomy; biology; chemistry; earth science; mathematics; physics; technology, agriculture, cars, computers, engineering, industry, inventions, communication","keywords":"astronomy; biology; chemistry; earth science; mathematics; physics; technology, agriculture, cars, computers, engineering, industry, inventions, communication","classId":"SCIENCE","sortOrder":2},"selectedNavbarLink":{"title":"Science & Tech","url":"/Science-Tech","selected":true,"navbarId":"SCIENCE"}} </script> <script id="json-hamburger-menu" type="application/json"> {"britannicaMenu1":[{"title":"Home","url":"/"},{"title":"ProCon","url":"/procon"},{"title":"History & Society","url":"/History-Society"},{"title":"Science & Tech","url":"/Science-Tech"},{"title":"Biographies","url":"/Biographies"},{"title":"Animals & Nature","url":"/Animals-Nature"},{"title":"Geography & Travel","url":"/Geography-Travel"},{"title":"Arts & Culture","url":"/Arts-Culture"},{"title":"Money","url":"/money"}],"britannicaMenu2":[{"title":"Games & Quizzes","url":"/quiz/browse"},{"title":"Videos","url":"/videos"},{"title":"On This Day","url":"/on-this-day"},{"title":"One Good Fact","url":"/one-good-fact"},{"title":"Dictionary","url":"/dictionary"},{"title":"New Articles","url":"/new-articles"}],"browseByCategory":[{"title":{"id":5,"title":"History & Society","url":"/History-Society"},"links":[{"title":"Lifestyles & Social Issues","url":"/browse/Lifestyles-Social-Issues"},{"title":"Philosophy & Religion","url":"/browse/Philosophy-Religion"},{"title":"Politics, Law & Government","url":"/browse/Politics-Law-Government"},{"title":"World History","url":"/browse/World-History"}]},{"title":{"id":6,"title":"Science & Tech","url":"/Science-Tech"},"links":[{"title":"Health & Medicine","url":"/browse/Health-Medicine"},{"title":"Science","url":"/browse/Science"},{"title":"Technology","url":"/browse/Technology"}]},{"title":{"id":3,"title":"Biographies","url":"/Biographies"},"links":[{"title":"Browse Biographies","url":"/browse/biographies"}]},{"title":{"id":1,"title":"Animals & Nature","url":"/Animals-Nature"},"links":[{"title":"Birds, Reptiles & Other Vertebrates","url":"/browse/Birds-Reptiles-Vertebrates"},{"title":"Bugs, Mollusks & Other Invertebrates","url":"/browse/Bugs-Mollusks-Invertebrates"},{"title":"Environment","url":"/browse/Environment"},{"title":"Fossils & Geologic Time","url":"/browse/Fossil-Geologic-Time"},{"title":"Mammals","url":"/browse/Mammals"},{"title":"Plants","url":"/browse/Plants"}]},{"title":{"id":4,"title":"Geography & Travel","url":"/Geography-Travel"},"links":[{"title":"Geography & Travel","url":"/browse/Geography-Travel"}]},{"title":{"id":2,"title":"Arts & Culture","url":"/Arts-Culture"},"links":[{"title":"Entertainment & Pop Culture","url":"/browse/Entertainment-Pop-Culture"},{"title":"Literature","url":"/browse/Literature"},{"title":"Sports & Recreation","url":"/browse/Sports-Recreation"},{"title":"Visual Arts","url":"/browse/Visual-Arts"}]}],"browseByFeature":[{"title":"Companions","url":"/stories/companion"},{"title":"Demystified","url":"/stories/demystified"},{"title":"Image Galleries","url":"/gallery/browse"},{"title":"Lists","url":"/list/browse"},{"title":"Podcasts","url":"/podcasts"},{"title":"Spotlight","url":"/stories/spotlight"},{"title":"Summaries","url":"/summary"},{"title":"The Forum","url":"/stories/the-forum"},{"title":"Top Questions","url":"/question"},{"title":"#WTFact","url":"/stories/wtfact"}],"moreFromBritannica":[{"title":"Britannica Kids","url":"https://kids.britannica.com/","newTab":true}],"menuType":"DEFAULT"} </script> <header id="header" class="bg-navy-dark"> <div class="global-nav-top-bar"> <div class="grid gx-0 h-100 justify-content-between align-items-center container-lg mx-auto p-0 position-relative"> <div class="d-flex align-items-center"> <button class="d-flex align-items-center justify-self-start js-toggle js-toggle-hamburger btn btn-link link-white btn-sm rounded-0 p-10"> <div class="hamburger-tooltip"> <em class="material-icons d-inline-block font-24" id="nav-toggle" data-icon="menu"></em> </div> <em class="material-icons d-inline-block font-24 global-nav-search-icon" id="nav-search-icon" data-icon="search" ></em> </button> <a href="/" class="d-flex align-items-center justify-content-center ml-10"> <img loading="lazy" src="https://cdn.britannica.com/mendel/eb-logo/MendelNewThistleLogo.png" alt="Encyclopedia Britannica" class="global-nav-logo global-nav-logo-left" /> </a> <div class="global-nav-top-search-bar global-nav-top-search-container global-nav-search-container" id="global-nav-top-search-bar"> <form method="get" action="/search" id="global-nav-search" class="md-search-form m-0 global-nav-search-bar-small"> <div class="search-box position-relative col-100"> <label class="sr-only" for="global-nav-search-query">Search Britannica</label> <input name="query" id="global-nav-search-query" placeholder="Search Britannica..." class="form-control form-control-lg rounded-lg font-16 search-query pl-20 pr-70 shadow-sm" maxlength="200" autocomplete="off" aria-label="Search Britannica" /> <button class="search-reset-btn btn btn-link px-10 position-absolute top-0 h-100 d-none" type="reset"> <em class="material-icons" data-icon="close"></em> </button> <button class="search-submit btn btn-link text-blue px-10 position-absolute top-0 right-0 h-100" type="submit" disabled> <span class="sr-only">Click here to search</span> <em class="material-icons search-icon" data-icon="search"></em> </button> </div> </form> </div> </div> <a href="/" class="d-flex align-items-center justify-content-center"> <img loading="lazy" src="https://cdn.britannica.com/mendel/eb-logo/MendelNewThistleLogo.png" alt="Encyclopedia Britannica" class="global-nav-center global-nav-logo non-homepage-logo" /> </a> <form method="get" action="/search" id="global-nav-search" class="md-search-form m-0 global-nav-search-bar-small global-nav-center search global-nav-center-search-container"> <div class="search-box position-relative col-100"> <label class="sr-only" for="global-nav-search-query">Search Britannica</label> <input name="query" id="global-nav-search-query" placeholder="Search Britannica..." class="form-control form-control-lg rounded-lg font-16 search-query pl-20 pr-70 shadow-sm" maxlength="200" autocomplete="off" aria-label="Search Britannica" /> <button class="search-reset-btn btn btn-link px-10 position-absolute top-0 h-100 d-none" type="reset"> <em class="material-icons" data-icon="close"></em> </button> <button class="search-submit btn btn-link text-blue px-10 position-absolute top-0 right-0 h-100" type="submit" disabled> <span class="sr-only">Click here to search</span> <em class="material-icons search-icon" data-icon="search"></em> </button> </div> </form> <div class="col-35 col-sm-auto text-right order-3 mr-lg-15 align-items-center d-flex justify-content-end"> <div class="d-none d-md-inline-block"> <SPAN class="marketing-HEADER_SUBSCRIPTION_DESKTOP2 marketing-content" data-marketing-id="HEADER_SUBSCRIPTION_DESKTOP2"><a href="https://subscription.britannica.com/subscribe?partnerCode=BP_Black_Friday_AUUS" class="subscribe-link btn btn-sm btn-outline-white-orange py-5 mr-10" target="_blank" rel="noopener"> Subscribe </a></SPAN></div> <div class="d-inline-block d-md-none mr-5 mr-sm-10"> <SPAN class="marketing-HEADER_SUBSCRIPTION_MOBILE marketing-content" data-marketing-id="HEADER_SUBSCRIPTION_MOBILE"><a href="https://subscription.britannica.com/subscribe?partnerCode=BP_Black_Friday_AUUS" class="subscribe-link btn btn-xs btn-orange-dark p-5" target="_blank" rel="noopener"> Subscribe </a></SPAN></div> <button class="js-toggle-user-dropdown js-toggle btn btn-sm btn-link link-white rounded-0 px-md-15 pl-5 pr-5"> <span class="d-none d-md-inline-block mr-5">Login</span> <em class="material-icons d-inline-block d-md-none font-16 font-sm-20" data-icon="account_circle"></em> <div class="d-none dropdown-menu-subscription-link">https://subscription.britannica.com/subscribe?partnerCode=BP_Black_Friday_AUUS</div> <em class="material-icons inactive-icon d-inline-block font-18" data-icon="keyboard_arrow_down"></em> <em class="material-icons active-icon d-inline-block font-18" data-icon="keyboard_arrow_up"></em> </button> </div> </div> </div> <div class="d-none hamburger-menu-subscription-link"><DIV class="marketing-HAMBURGER_MENU_CTA marketing-content" data-marketing-id="HAMBURGER_MENU_CTA"><a href="https://premium.britannica.com/premium-membership/?utm_source=premium&utm_medium=hamburger-menu&utm_campaign=black-friday-2024" class="subscribe-link btn btn-sm btn-orange py-5" target="_blank"> Subscribe <span class="d-none d-md-inline"> Now</span> </a></DIV></div> <div id="global-nav-react"> <div class="d-none"> <ul> <li><a href="/">Home</a></li> <li><a href="/procon">ProCon</a></li> <li><a href="/History-Society">History & Society</a></li> <li><a href="/Science-Tech">Science & Tech</a></li> <li><a href="/Biographies">Biographies</a></li> <li><a href="/Animals-Nature">Animals & Nature</a></li> <li><a href="/Geography-Travel">Geography & Travel</a></li> <li><a href="/Arts-Culture">Arts & Culture</a></li> <li><a href="/money">Money</a></li> </ul> <ul> <li><a href="/quiz/browse">Games & Quizzes</a></li> <li><a href="/videos">Videos</a></li> <li><a href="/on-this-day">On This Day</a></li> <li><a href="/one-good-fact">One Good Fact</a></li> <li><a href="/dictionary">Dictionary</a></li> <li><a href="/new-articles">New Articles</a></li> </ul> <a href="/History-Society">History & Society</a> <ul> <li><a href="/browse/Lifestyles-Social-Issues">Lifestyles & Social Issues</a></li> <li><a href="/browse/Philosophy-Religion">Philosophy & Religion</a></li> <li><a href="/browse/Politics-Law-Government">Politics, Law & Government</a></li> <li><a href="/browse/World-History">World History</a></li> </ul> <a href="/Science-Tech">Science & Tech</a> <ul> <li><a href="/browse/Health-Medicine">Health & Medicine</a></li> <li><a href="/browse/Science">Science</a></li> <li><a href="/browse/Technology">Technology</a></li> </ul> <a href="/Biographies">Biographies</a> <ul> <li><a href="/browse/biographies">Browse Biographies</a></li> </ul> <a href="/Animals-Nature">Animals & Nature</a> <ul> <li><a href="/browse/Birds-Reptiles-Vertebrates">Birds, Reptiles & Other Vertebrates</a></li> <li><a href="/browse/Bugs-Mollusks-Invertebrates">Bugs, Mollusks & Other Invertebrates</a></li> <li><a href="/browse/Environment">Environment</a></li> <li><a href="/browse/Fossil-Geologic-Time">Fossils & Geologic Time</a></li> <li><a href="/browse/Mammals">Mammals</a></li> <li><a href="/browse/Plants">Plants</a></li> </ul> <a href="/Geography-Travel">Geography & Travel</a> <ul> <li><a href="/browse/Geography-Travel">Geography & Travel</a></li> </ul> <a href="/Arts-Culture">Arts & Culture</a> <ul> <li><a href="/browse/Entertainment-Pop-Culture">Entertainment & Pop Culture</a></li> <li><a href="/browse/Literature">Literature</a></li> <li><a href="/browse/Sports-Recreation">Sports & Recreation</a></li> <li><a href="/browse/Visual-Arts">Visual Arts</a></li> </ul> <ul> <li><a href="/stories/companion">Companions</a></li> <li><a href="/stories/demystified">Demystified</a></li> <li><a href="/gallery/browse">Image Galleries</a></li> <li><a href="/list/browse">Lists</a></li> <li><a href="/podcasts">Podcasts</a></li> <li><a href="/stories/spotlight">Spotlight</a></li> <li><a href="/summary">Summaries</a></li> <li><a href="/stories/the-forum">The Forum</a></li> <li><a href="/question">Top Questions</a></li> <li><a href="/stories/wtfact">#WTFact</a></li> </ul> <ul> <li><a href="https://kids.britannica.com/">Britannica Kids</a></li> </ul> </div> </div> </header> <div class="bg-navy-dark"> <div class="container-lg p-0 d-flex justify-content-center global-nav-categories-bar overflow-hidden"> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 global-nav-slider category-snap-slider"> <div class="slider-container js-slider-container overflow-hidden d-flex font-14 overflow-hidden text-nowrap mx-5"> <a class="nav-bar-category mx-5 category-link-CHATBOT " href="/chatbot">Ask the Chatbot</a> <a class="nav-bar-category mx-5 category-link-QUIZZES " href="/quiz/browse">Games & Quizzes</a> <a class="nav-bar-category mx-5 category-link-PROCON " href="/procon">ProCon</a> <a class="nav-bar-category mx-5 category-link-HISTORY " href="/History-Society">History & Society</a> <a class="nav-bar-category mx-5 category-link-SCIENCE selected selected" href="/Science-Tech">Science & Tech</a> <a class="nav-bar-category mx-5 category-link-BIOS " href="/Biographies">Biographies</a> <a class="nav-bar-category mx-5 category-link-ANIMALS " href="/Animals-Nature">Animals & Nature</a> <a class="nav-bar-category mx-5 category-link-GEOGRAPHY " href="/Geography-Travel">Geography & Travel</a> <a class="nav-bar-category mx-5 category-link-ART " href="/Arts-Culture">Arts & Culture</a> <a class="nav-bar-category mx-5 category-link-MONEY " href="/money">Money</a> <a class="nav-bar-category mx-5 category-link-VIDEOS " href="/videos">Videos</a> </div> <button disabled class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-blue " aria-label="Previous"> <span class="material-icons md-24" data-icon="keyboard_arrow_left"></span> </button> <button disabled class="next-button js-next-button position-absolute btn btn-circle shadow btn-blue " aria-label="Next"> <span class="material-icons md-24" data-icon="keyboard_arrow_right"></span> </button> </div> </div> </div> <main> <div class="md-page-wrapper"> <div id="content" class="md-content"> <div class="grid gx-0 container-lg px-0 py-lg-20 mx-auto"> <div class="col-auto"> <div class="topic-left-rail md-article-drawer position-relative d-flex border-right-sm border-left-sm open"> <div class="drawer d-flex flex-column open"> <div class="left-rail-section-content"> <div class="topic-left-rail-header text-truncate bg-gray-50 position-relative text-right d-flex align-items-center"> <div class="tlr-title px-20 py-15 text-left"> <em class="material-icons text-gray-400 d-lg-none" data-icon="toc"></em> <a class="font-serif font-weight-bold text-black link-blue" href="https://www.britannica.com/science/isotope">isotope</a> </div> <button aria-label="Close" class="js-sections-close-button btn-link btn-sm btn d-lg-none position-absolute top-0 p-10 right-0" > <em class="material-icons font-26" data-icon="close"></em> </button> </div> <div class="section-content pl-10 pr-20 pl-sm-50 pr-sm-60 pl-lg-5 pr-lg-10 pt-10 pt-lg-0 bg-gray-50 clear-catfish-ad"> <div class="toc mb-20"> <div class="font-serif font-14 font-weight-bold mx-15 mb-15 mt-20"> Table of Contents </div> <ul class="list-unstyled my-0" data-level="h1"><li data-target="#ref1"><div class="pl-25"><a class="link-gray-900 w-100" href="/science/isotope">Introduction & Top Questions</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref48249"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/science/isotope/The-discovery-of-isotopes">The discovery of isotopes</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref48250"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/science/isotope/The-discovery-of-isotopes#ref48250">Nuclear stability</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref48251"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/science/isotope/The-discovery-of-isotopes#ref48251">Radioactive isotopes</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref48252"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/science/isotope/Elemental-and-isotopic-abundances">Elemental and isotopic abundances</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref48253"><div class="d-flex align-items-center"><button class="h1-link-drawer-button btn btn-xs btn-circle d-flex rounded" type="button" aria-label="Toggle Heading"><em class="material-icons font-18" data-icon="keyboard_arrow_right"></em></button><a class="w-100 link-gray-900" href="/science/isotope/Variations-in-isotopic-abundances">Variations in isotopic abundances</a></div><div class="ml-40 toc-drawer sub-toc-drawer"><ul class="list-unstyled" data-level="h2"><li data-target="#ref48254"><a class="w-100 link-gray-900" href="/science/isotope/Variations-in-isotopic-abundances#ref48254">Radioactive decay</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref48255"><a class="w-100 link-gray-900" href="/science/isotope/Variations-in-isotopic-abundances#ref48255">Mass fractionation</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref48256"><a class="w-100 link-gray-900" href="/science/isotope/Variations-in-isotopic-abundances#ref48256">Other causes of isotopic abundance variations</a></li></ul></div></li><li data-target="#ref48257"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/science/isotope/Variations-in-isotopic-abundances#ref48257">Physical properties associated with isotopes</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref48258"><div class="d-flex align-items-center"><button class="h1-link-drawer-button btn btn-xs btn-circle d-flex rounded" type="button" aria-label="Toggle Heading"><em class="material-icons font-18" data-icon="keyboard_arrow_right"></em></button><a class="w-100 link-gray-900" href="/science/isotope/Variations-in-isotopic-abundances#ref48258">Effect of isotopes on atomic and molecular spectra</a></div><div class="ml-40 toc-drawer sub-toc-drawer"><ul class="list-unstyled" data-level="h2"><li data-target="#ref48259"><a class="w-100 link-gray-900" href="/science/isotope/Molecular-vibrations">Molecular vibrations</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref48260"><a class="w-100 link-gray-900" href="/science/isotope/Molecular-vibrations#ref48260">Importance in the study of polyatomic molecules</a></li></ul></div></li><li data-target="#ref48261"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/science/isotope/Molecular-vibrations#ref48261">Chemical effects of isotopic substitution</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref48262"><div class="d-flex align-items-center"><div class="ml-25"></div><a class="w-100 link-gray-900" href="/science/isotope/Molecular-vibrations#ref48262">Effect of isotopic substitution on reaction rates</a></div><div class="ml-40 toc-drawer sub-toc-drawer"></div></li><li data-target="#ref48263"><div class="d-flex align-items-center"><button class="h1-link-drawer-button btn btn-xs btn-circle d-flex rounded" type="button" aria-label="Toggle Heading"><em class="material-icons font-18" data-icon="keyboard_arrow_right"></em></button><a class="w-100 link-gray-900" href="/science/isotope/Isotope-separation-and-enrichment">Isotope separation and enrichment</a></div><div class="ml-40 toc-drawer sub-toc-drawer"><ul class="list-unstyled" data-level="h2"><li data-target="#ref48264"><a class="w-100 link-gray-900" href="/science/isotope/Isotope-separation-and-enrichment#ref48264">Mass spectrometry</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref48265"><a class="w-100 link-gray-900" href="/science/isotope/Isotope-separation-and-enrichment#ref48265">Distillation</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref48266"><a class="w-100 link-gray-900" href="/science/isotope/Isotope-separation-and-enrichment#ref48266">Chemical exchange reactions</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref48267"><a class="w-100 link-gray-900" href="/science/isotope/Isotope-separation-and-enrichment#ref48267">Gaseous diffusion</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref48268"><a class="w-100 link-gray-900" href="/science/isotope/Isotope-separation-and-enrichment#ref48268">Gas centrifugation</a></li></ul><ul class="list-unstyled" data-level="h2"><li data-target="#ref48269"><a class="w-100 link-gray-900" href="/science/isotope/Isotope-separation-and-enrichment#ref48269">Photochemical enrichment methods</a></li></ul></div></li></ul> <a class="toc-extra-link link-gray-900" href="https://www.britannica.com/science/isotope/additional-info">References & Edit History</a> <a class="toc-extra-link link-gray-900" href="/facts/isotope">Related Topics</a> </div> <div class="tlr-media-slider pb-10 mb-30"> <a class="section-header link-gray-900 font-serif font-14 font-weight-bold mb-10 mx-10 selected" href="https://www.britannica.com/science/isotope/images-videos">Images & Videos</a> <div class="slider js-slider position-relative d-inline-flex align-items-center mw-100 "> <div class="slider-container js-slider-container overflow-hidden d-flex overflow-hidden text-nowrap ml-15"> <a href="/video/What-are-isotopes/246891" data-href="/media/1/296583/246891" class="media-overlay-link d-inline-block mr-5"> <div class="position-relative --aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/64/216564-138-51A467D7/What-are-isotopes.jpg?w=400&h=225&c=crop" alt="What are isotopes and how do they work?" class="col-100" /> <div class="btn btn-sm btn-white btn-circle position-absolute shadow" style="top: 50%; left:50%; transform: translate(-50%, -50%)"> <em class="material-icons font-14" data-icon="play_arrow" > </em> </div> </div> </a> <a href="/video/Nuclear-medicine-overview-radioisotope-tracers/245556" data-href="/media/1/296583/245556" class="media-overlay-link d-inline-block mr-5"> <div class="position-relative --aspect-ratio: 16/9"> <img loading="lazy" src="https://cdn.britannica.com/10/214810-138-173775E6/Nuclear-medicine-overview-radioisotope-tracers.jpg?w=400&h=225&c=crop" alt="How are radioisotopes used in medical diagnosis and treatment?" class="col-100" /> <div class="btn btn-sm btn-white btn-circle position-absolute shadow" style="top: 50%; left:50%; transform: translate(-50%, -50%)"> <em class="material-icons font-14" data-icon="play_arrow" > </em> </div> </div> </a> <a href="https://cdn.britannica.com/51/6051-004-FBE0B587/phase-diagrams-helium-3-show-isotopes-helium-4-states.jpg" data-href="/media/1/296583/662" class="media-overlay-link d-inline-block mr-5"> <img loading="lazy" src="https://cdn.britannica.com/51/6051-004-FBE0B587/phase-diagrams-helium-3-show-isotopes-helium-4-states.jpg" alt="phase diagrams of helium-3 and helium-4" height="50" /> </a> </div> <button disabled class="prev-button js-prev-button position-absolute btn btn-circle shadow btn-blue " aria-label="Previous"> <span class="material-icons md-24" data-icon="keyboard_arrow_left"></span> </button> <button disabled class="next-button js-next-button position-absolute btn btn-circle shadow btn-blue " aria-label="Next"> <span class="material-icons md-24" data-icon="keyboard_arrow_right"></span> </button> </div> </div> <div class="mb-30 tlr-student-links"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> For Students </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/summary/isotope"> <img loading="lazy" src="https://cdn.britannica.com/mendel-resources/3-130/images/shared/default3.png?v=3.130.14" class="default " height="200" width="200"/> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/summary/isotope" >isotope summary</a> </div> </div> </div> <div class="mb-30 tlr-related-quizzes"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> Quizzes </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/quiz/facts-you-should-know-the-periodic-table-quiz"> <img loading="lazy" src="https://cdn.britannica.com/58/203458-131-D94E9327/periodic-table-concept.jpg?w=200&h=200&c=crop" alt="Periodic Table of the elements concept image (chemistry)" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/quiz/facts-you-should-know-the-periodic-table-quiz" >Facts You Should Know: The Periodic Table Quiz</a> </div> </div> </div> <div class="mb-30 tlr-related-questions"> <div class="text-gray-900 p-5 pb-0 font-serif font-14 font-weight-bold mx-10 mb-15"> Related Questions </div> <ul> <li class="link-gray-900 mb-15"><a class="" href="/question/When-are-isotopes-stable">When are isotopes stable?</a> </li> </ul> </div> <div class="mb-30 tlr-discover"> <div class="text-gray-900 p-5 font-serif font-14 font-weight-bold mx-10 mb-10"> Discover </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/9-queer-writers-you-should-read"> <img loading="lazy" src="https://cdn.britannica.com/60/144760-131-5E258FAB/Rainbow-flag-Sign-diversity-Gilbert-Baker-hope-1978.jpg?w=200&h=200&c=crop" alt="Rainbow flag. Sign of diversity, inclusiveness, hope, yearning. Gay pride flag popularized by San Francisco artist Gilbert Baker in 1978. Inspired by Judy Garland singing Over the Rainbow. gay rights, homosexual, gays, LGBT community" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/9-queer-writers-you-should-read" >13 LGBTQ Writers You Should Read</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/6-lost-civilizations"> <img loading="lazy" src="https://cdn.britannica.com/15/95015-131-5E505098/statues-Moai-Easter-Island.jpg?w=200&h=200&c=crop" alt="Panoramic view at sunrise of moai, Ahu Tongariki, Easter Island (Rapa Nui), Chile" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/6-lost-civilizations" >6 Lost Civilizations</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/why-is-thanksgiving-in-the-us-celebrated-on-a-thursday"> <img loading="lazy" src="https://cdn.britannica.com/06/212906-131-C791368A/Thanksgiving-celebration-food-table-spread.jpg?w=200&h=200&c=crop" alt="Thanksgiving Celebration Traditional Dinner Setting Food Concept" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/why-is-thanksgiving-in-the-us-celebrated-on-a-thursday" >Why Is Thanksgiving in the U.S. Celebrated on a Thursday?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/how-do-black-holes-really-work"> <img loading="lazy" src="https://cdn.britannica.com/84/193284-131-66EAF092/merging-black-holes-binary-system-each-other-December-26-2015.jpg?w=200&h=200&c=crop" alt="The merger of two black holes and the gravitational waves that ripple outward as the black holes spiral toward each other. The black holes-which represent those detected by LIGO on Dec. 26, 2015-were 14 and 8 times the mass of the sun, until they merged," width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/how-do-black-holes-really-work" >How Do Black Holes Really Work?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/story/where-do-anti-semitic-conspiracy-theories-about-the-rothschild-family-come-from"> <img loading="lazy" src="https://cdn.britannica.com/67/200267-131-4F79E2AC/Mayer-Amschel-Rothschild.jpg?w=200&h=200&c=crop" alt="Mayer Amschel Rothschild (1744-1855), founder of the house of Rothschild; lithograph by Friedrich Lieder, c. 1830." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/story/where-do-anti-semitic-conspiracy-theories-about-the-rothschild-family-come-from" >Where Do Anti-Semitic Conspiracy Theories About the Rothschild Family Come From?</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/secret-service-code-names-of-11-us-presidents"> <img loading="lazy" src="https://cdn.britannica.com/45/189145-131-45FF672E/Secret-Service-Agent-Earpiece.jpg?w=200&h=200&c=crop" alt="Secret Service Agent Listens To Earpiece" width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/secret-service-code-names-of-11-us-presidents" >Secret Service Code Names of 11 U.S. Presidents</a> </div> </div> <div class="imagelink-with-image-on-the-side card card-horizontal tlr-img-with-side-link ml-15 link-gray-900 mb-10" > <div class="position-relative card-media" style="flex: 0;"> <a class="ilf-image position-relative" href="/list/13-iconic-buildings-to-visit-in-new-york-city"> <img loading="lazy" src="https://cdn.britannica.com/82/156482-131-AEEBFEFC/New-York-York.jpg?w=200&h=200&c=crop" alt="New York city skyline aerial with the Empire State Building, New York City, New York." width="200" height="200" /> </a> </div> <div class="card-body ilf-content"> <a class="font-weight-semi-bold d-block mb-5 font-16 ilf-title" href="/list/13-iconic-buildings-to-visit-in-new-york-city" >13 Iconic Buildings to Visit in New York City</a> </div> </div> </div> </div> </div> </div> <button class="drawerToggle btn position-sticky border btn-xs btn-white btn-circle rounded-sm d-none d-lg-flex " type="button" aria-label="Toggle Drawer"> <em class="material-icons font-18 text-blue" data-icon="keyboard_arrow_left"></em> </button> </div> </div> <div class="col"> <div class="toc-sticky-header d-none d-lg-none bg-gray-50 px-10 px-sm-30 position-sticky w-100 "> <div class="toc-sticky-header-inner-container align-items-center d-flex mx-auto h-100 w-100"> <button class="d-flex d-lg-none btn btn-sm btn-white text-blue border-2 border-gray-100 gtm-mobile-toc-header-button js-sections-button d-lg-none p-10"> <em class="material-icons my-n5 md-icon" data-icon="toc"></em> Contents </button> <div class="header-ai-ask-button-placeholder"></div> <div class="header-ai-summarize-button-placeholder"></div> </div> </div> <div class="grey-box w-100 grey-box-middle"> <div class="grey-box-content mx-auto w-100"> <script type="application/ld+json"> { "@context" : "https://schema.org", "@type" : "BreadcrumbList", "itemListElement" : [ { "@type" : "ListItem", "position" : 1, "item" : { "@id" : "https://www.britannica.com/browse/Science", "name": "Science" } } , { "@type" : "ListItem", "position" : 2, "item" : { "@id" : "https://www.britannica.com/browse/Chemistry", "name": "Chemistry" } } ] } </script> <nav class="breadcrumb mt-20 mb-30"> <span class="breadcrumb-item "> <a href="/" class="link-gray-600">Home</a> </span> <span class="breadcrumb-item "> <a class="link-gray-600" href="/browse/Science">Science</a> </span> <span class="breadcrumb-item "> <a class="link-gray-600" href="/browse/Chemistry">Chemistry</a> </span> </nav> <h1>isotope: Media</h1> <div class="font-20 font-serif">chemistry</div> <div class="md-topic-tools mt-15 mb-15 qa-action-buttons"> <button class="js-share-modal-button js-modal gtm-topic-tool btn btn-xs btn-outline-blue border shadow-sm pr-10" data-modal=".md-share-modal"> <em class="material-icons md-icon ml-n10 my-n5 mr-5" data-icon="share"></em> Share </button> <div class="md-share-modal size-lg d-none qa-share-modal"> <div class="md-modal-body"> <div class="h2 font-serif d-flex align-items-center pb-15 border-bottom"> <em class="material-icons text-blue mr-10" data-icon="share"></em> Share </div> <div class="label my-20">Share to social media</div> <div class="md-social-toolbar-circle d-flex align-items-start inverted" data-value="share" title="isotope (chemistry)" data-url="https://www.britannica.com/science/isotope/images-videos" > <a class="social-icon facebook justify-content-center d-flex align-items-center align-self-center" data-provider="facebook" href="https://www.facebook.com/BRITANNICA/" target="_blank" rel="noopener"><span>Facebook</span></a> <a class="social-icon x justify-content-center d-flex align-items-center align-self-center" data-provider="x" href="https://x.com/britannica" target="_blank" rel="noopener"><span>X</span></a> </div> <div class="label pt-20 mt-20 mb-5 border-top">URL</div> <a class="font-serif text-truncate d-inline-block" href="https://www.britannica.com/science/isotope/images-videos">https://www.britannica.com/science/isotope/images-videos</a> </div> </div> </div> <div id="md-topic-media-browse-list"> <div id="Videos"> <div id="Videos-isotope" class="pt-20 pb-30 border-top "> <h2> Videos</h2> </div> <div class="grid g-20"> <div class="md-topic-media-browse-list-item col-50 col-sm-33 col-lg-25 md-topic-media-browse-video"> <div style="--aspect-ratio: 16/9"> <a href="https://www.britannica.com/video/What-are-isotopes/-246891" class="w-100 d-flex justify-content-center align-items-center media-overlay-link bg-black" data-href="/media/1/296583/246891"> <img loading="lazy" src="https://cdn.britannica.com/64/216564-138-51A467D7/What-are-isotopes.jpg?w=315" alt="What are isotopes and how do they work?" class="o-70 h-100" /> <div class="position-absolute top-0 left-0 h-100 w-100 d-flex justify-content-center align-items-center"> <em class="material-icons link-white md-36" data-icon="play_arrow"></em> </div> </a> </div> <a href="https://www.britannica.com/video/What-are-isotopes/-246891" class="font-weight-bold font-12 lh-sm my-10 d-block media-overlay-link " data-href="/media/1/296583/246891"> What are isotopes and how do they work?</a> <div class="font-serif font-12 lh-sm my-10 d-none d-sm-block"> An overview of isotopes.</div> <div class="caption lh-sm mt-10"> Video: 漏 American Chemical Society (<a class="external" target="_blank" rel="noopener" href="http://corporate.britannica.com/partners" data-show-preview="true">A Britannica Publishing Partner</a>)</div> </div> <div class="md-topic-media-browse-list-item col-50 col-sm-33 col-lg-25 md-topic-media-browse-video"> <div style="--aspect-ratio: 16/9"> <a href="https://www.britannica.com/video/Nuclear-medicine-overview-radioisotope-tracers/-245556" class="w-100 d-flex justify-content-center align-items-center media-overlay-link bg-black" data-href="/media/1/296583/245556"> <img loading="lazy" src="https://cdn.britannica.com/10/214810-138-173775E6/Nuclear-medicine-overview-radioisotope-tracers.jpg?w=315" alt="How are radioisotopes used in medical diagnosis and treatment?" class="o-70 h-100" /> <div class="position-absolute top-0 left-0 h-100 w-100 d-flex justify-content-center align-items-center"> <em class="material-icons link-white md-36" data-icon="play_arrow"></em> </div> </a> </div> <a href="https://www.britannica.com/video/Nuclear-medicine-overview-radioisotope-tracers/-245556" class="font-weight-bold font-12 lh-sm my-10 d-block media-overlay-link " data-href="/media/1/296583/245556"> How are radioisotopes used in medical diagnosis and treatment?</a> <div class="font-serif font-12 lh-sm my-10 d-none d-sm-block"> Overview of applications of radioisotopes as tracers in nuclear medicine.</div> <div class="caption lh-sm mt-10"> Video: Encyclop忙dia Britannica, Inc.</div> </div> </div> </div> <div id="Images"> <div id="Images-isotope" class="pt-20 pb-30 border-top mt-40"> <h2> Images</h2> </div> <div class="grid g-20"> <div class="md-topic-media-browse-list-item col-50 col-sm-33 col-lg-25 md-topic-media-browse-image"> <div style="--aspect-ratio: 16/9"> <a href="https://cdn.britannica.com/51/6051-004-FBE0B587/phase-diagrams-helium-3-show-isotopes-helium-4-states.jpg" class="w-100 d-flex justify-content-center align-items-center media-overlay-link " data-href="/media/1/296583/662"> <img loading="lazy" src="https://cdn.britannica.com/51/6051-004-FBE0B587/phase-diagrams-helium-3-show-isotopes-helium-4-states.jpg?w=315" alt="phase diagrams of helium-3 and helium-4" /> <button class="btn btn-circle position-absolute shadow btn-white" aria-label="Zoom in"> <em class="material-icons link-blue" data-icon="zoom_in"></em> </button> </a> </div> <a href="https://cdn.britannica.com/51/6051-004-FBE0B587/phase-diagrams-helium-3-show-isotopes-helium-4-states.jpg" class="font-weight-bold font-12 lh-sm my-10 d-block media-overlay-link " data-href="/media/1/296583/662"> phase diagrams of helium-3 and helium-4</a> <div class="font-serif font-12 lh-sm my-10 d-none d-sm-block"> The phase diagrams of (A) helium-3 and (B) helium-4 show which states of these isotopes...</div> <div class="credit lh-sm mt-10"> Encyclop忙dia Britannica, Inc.</div> </div> </div> </div> </div> <div class="border-top-10 border-top-blue-dark my-50 border-bottom"> <div class="font-20 py-20"><strong>VIEW MORE</strong> in these related Britannica articles:</div> <ul class="list-unstyled md-topic-media-related grid"> <li class="col-md-25 col-50"> <a href="https://www.britannica.com/science/transuranium-element/images-videos"> <img loading="lazy" src="https://cdn.britannica.com/45/7445-050-BB332C27/version-periodic-table-elements.jpg?w=300&h=150" alt="periodic table" /> <div class="title mt-10">Media for: transuranium element</div> </a> </li> <li class="col-md-25 col-50"> <a href="https://www.britannica.com/science/uranium-235/images-videos"> <img loading="lazy" src="https://cdn.britannica.com/92/62992-050-D75534B6/neutron-impact-nuclei-nucleus-uranium-isotope-any.jpg?w=300&h=150" alt="Nuclear fission" /> <div class="title mt-10">Media for: uranium-235</div> </a> </li> </ul> </div> </div> </div> </div> </div></div> </div> </main> <div id="md-footer"></div> <footer class="md-footer footer-wrapper hide-on-edit"> <div class="footer-bck"> <DIV class="marketing-FOOTER_NEWSLETTER marketing-content" data-marketing-id="FOOTER_NEWSLETTER"><div class="md-footer-newsletter-form pt-10 mb-30 mx-15 mx-sm-120"> <div class="font-18"> <strong>History at your fingertips –</strong> Sign up here to see what happened On This Day, every day in your inbox! </div> <div class="p-30"> <div class="newsletter-form-container"> <form class="newsletter-form" method="post" action="/newsletter-subscription/EB_ON_THIS_DAY"> <div class="form-group grid d-flex justify-content-center"> <div class="col-sm-50 col-100"> <label class="sr-only" for="enter-your-email">Enter your email</label> <input id="enter-your-email" type="email" name="email" class="form-control font-18 p-10" placeholder="Enter your email" pattern="[a-z0-9._%+-]+@[a-z0-9.-]+\.[a-z]{2,4}$" required> </div> <div class="col-sm-auto col-100 mt-5 mt-sm-0"> <button type="submit" class="btn btn-outline-white" style="width: 100%; height:100%;">Subscribe</button> </div> </div> <div class="text-white pt-30 text-opacity"> By signing up for this email, you are agreeing to news, offers, and information from Encyclopaedia Britannica.<br> Click here to view our <a class="link-white text-decoration-underline" href="https://corporate.britannica.com/privacy-policy2" target="_blank" rel="noopener nofollow">Privacy Notice</a>. Easy unsubscribe links are provided in every email. </div> <input type="hidden" name="source" value="Footer" /><input type="hidden" name="campaign" value="Mendel" /><input type="hidden" name="medium" value="Box" /></form> <div class="md-subscribed hidden text-white"> <div class="my-10">Thank you for subscribing!</div> <div>Be on the lookout for your Britannica newsletter to get trusted stories delivered right to your inbox.</div> </div> </div> </div> </div></DIV> <div class="md-social-toolbar-circle d-flex justify-content-center colored" data-value="connect" > <div class="share-label text-uppercase hidden-xs">Stay Connected</div> <a class="social-icon facebook justify-content-center d-flex align-items-center align-self-center" data-provider="facebook" href="https://www.facebook.com/BRITANNICA/" target="_blank" rel="noopener"><span>Facebook</span></a> <a class="social-icon x justify-content-center d-flex align-items-center align-self-center" data-provider="x" href="https://x.com/britannica" target="_blank" rel="noopener"><span>X</span></a> <a class="social-icon youtube justify-content-center d-flex align-items-center align-self-center" data-provider="youtube" href="https://www.youtube.com/c/encyclopaediabritannica" target="_blank" rel="noopener"><span>YouTube</span></a> <a class="social-icon instagram justify-content-center d-flex align-items-center align-self-center" data-provider="instagram" href="https://www.instagram.com/britannica/" target="_blank" rel="noopener"><span>Instagram</span></a> <a class="social-icon pinterest justify-content-center d-flex align-items-center align-self-center" data-provider="pinterest" href="https://www.pinterest.com/britannica/" target="_blank" rel="noopener"> <svg height="30" width="30" viewBox="0 0 24 24" aria-hidden="true" aria-label="" role="img"><path d="M0 12c0 5.123 3.211 9.497 7.73 11.218-.11-.937-.227-2.482.025-3.566.217-.932 1.401-5.938 1.401-5.938s-.357-.715-.357-1.774c0-1.66.962-2.9 2.161-2.9 1.02 0 1.512.765 1.512 1.682 0 1.025-.653 2.557-.99 3.978-.281 1.189.597 2.159 1.769 2.159 2.123 0 3.756-2.239 3.756-5.471 0-2.861-2.056-4.86-4.991-4.86-3.398 0-5.393 2.549-5.393 5.184 0 1.027.395 2.127.889 2.726a.36.36 0 0 1 .083.343c-.091.378-.293 1.189-.332 1.355-.053.218-.173.265-.4.159-1.492-.694-2.424-2.875-2.424-4.627 0-3.769 2.737-7.229 7.892-7.229 4.144 0 7.365 2.953 7.365 6.899 0 4.117-2.595 7.431-6.199 7.431-1.211 0-2.348-.63-2.738-1.373 0 0-.599 2.282-.744 2.84-.282 1.084-1.064 2.456-1.549 3.235C9.584 23.815 10.77 24 12 24c6.627 0 12-5.373 12-12S18.627 0 12 0 0 5.373 0 12"></path></svg> </a> </div> <br/> <div class="container"> <ul class="list-unstyled legal-links"> <li><a href="https://corporate.britannica.com" rel="noopener" target="_blank">About Us & Legal Info</a></li> <li><a href="https://corporate.britannica.com/contact/" target="_blank" rel="noopener nofollow">Contact Us</a></li> <li><a href="https://corporate.britannica.com/privacy-policy2" target="_blank" rel="noopener nofollow">Privacy Policy</a></li> <li><a href="https://corporate.britannica.com/termsofuse.html2" target="_blank" rel="noopener nofollow">Terms of Use</a></li> <li><a href="https://corporate.britannica.com/diversity" target="_blank" rel="noopener nofollow">Diversity</a></li> </ul> <div class="mt-20">©2024 Encyclopædia Britannica, Inc.</div> </div> </div> </footer> <noscript><iframe src="//www.googletagmanager.com/ns.html?id=GTM-5W6NC8" height="0" width="0" style="display:none;visibility:hidden"></iframe></noscript> <script type="text/javascript" id="_informizely_script_tag"> var IzWidget = IzWidget || {}; (function (d) { var scriptElement = d.createElement('script'); scriptElement.type = 'text/javascript'; scriptElement.async = true; scriptElement.src = "https://insitez.blob.core.windows.net/site/f780f33e-a610-4ac2-af81-3eb184037547.js"; var node = d.getElementById('_informizely_script_tag'); node.parentNode.insertBefore(scriptElement, node); } )(document); </script> <!-- Ortto ebmwprod capture code --> <script> window.ap3c = window.ap3c || {}; var ap3c = window.ap3c; ap3c.cmd = ap3c.cmd || []; ap3c.cmd.push(function() { ap3c.init('ZO4siT4cLwnykPnzZWJtd3Byb2Q', 'https://engage.email.britannica.com/'); ap3c.track({v: 0}); }); ap3c.activity = function(act) { ap3c.act = (ap3c.act || []); ap3c.act.push(act); }; var s, t; s = document.createElement('script'); s.type = 'text/javascript'; s.src = "https://engage.email.britannica.com/app.js"; t = document.getElementsByTagName('script')[0]; t.parentNode.insertBefore(s, t); </script> <script class="marketing-page-info" type="application/json"> {"pageType":"TopicMediaBrowse","templateName":null,"pageNumber":1,"pagesTotal":1,"pageId":null,"pageLength":null,"initialLoad":true,"lastPageOfScroll":true} </script> <script class="marketing-content-info" type="application/json"> [] </script> <script src="https://cdn.britannica.com/mendel-resources/3-130/js/libs/jquery-3.5.0.min.js?v=3.130.14"></script> <script type="text/javascript" data-type="Init Mendel Code Splitting"> (function() { $.ajax({ dataType: 'script', cache: true, url: 'https://cdn.britannica.com/mendel-resources/3-130/dist/topic-media-browse-page.js?v=3.130.14' }); })(); </script> <script class="analytics-metadata" type="application/json"> {"leg":"A","adLeg":"A","userType":"ANONYMOUS","pageType":"TopicMediaBrowse","pageSubtype":null,"articleTemplateType":null,"gisted":false,"pageNumber":1,"hasSummarizeButton":false,"hasAskButton":false} </script> <script type="text/javascript"> EBStat={accountId:-1,hostnameOverride:'webstats.eb.com',domain:'www.britannica.com', json:''}; </script> <script type="text/javascript"> ( function() { $.ajax( { dataType: 'script', cache: true, url: '//www.britannica.com/webstats/mendelstats.js?v=1' } ) .done( function() { try {writeStat(null,EBStat);} catch(err){} } ); })(); </script> <div id="bc-fixed-dialogue"></div> </body> </html>