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id="toc-mw-content-text" class="vector-toc-list-item vector-toc-level-1"> <a href="#" class="vector-toc-link"> <div class="vector-toc-text">Início</div> </a> </li> <li id="toc-Definição" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Definição"> <div class="vector-toc-text"> <span class="vector-toc-numb">1</span> <span>Definição</span> </div> </a> <ul id="toc-Definição-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Massa_molecular" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Massa_molecular"> <div class="vector-toc-text"> <span class="vector-toc-numb">2</span> <span>Massa molecular</span> </div> </a> <ul id="toc-Massa_molecular-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Escrita" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Escrita"> <div class="vector-toc-text"> <span class="vector-toc-numb">3</span> <span>Escrita</span> </div> </a> <ul id="toc-Escrita-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Desenvolvimento_histórico_do_termo" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Desenvolvimento_histórico_do_termo"> <div class="vector-toc-text"> <span class="vector-toc-numb">4</span> <span>Desenvolvimento histórico do termo</span> </div> </a> <ul id="toc-Desenvolvimento_histórico_do_termo-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Ver_também" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Ver_também"> <div class="vector-toc-text"> <span class="vector-toc-numb">5</span> <span>Ver também</span> </div> </a> <ul id="toc-Ver_também-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Bibliografia" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Bibliografia"> <div class="vector-toc-text"> <span class="vector-toc-numb">6</span> <span>Bibliografia</span> </div> </a> <ul id="toc-Bibliografia-sublist" class="vector-toc-list"> </ul> </li> <li id="toc-Ligações_externas" class="vector-toc-list-item vector-toc-level-1 vector-toc-list-item-expanded"> <a class="vector-toc-link" href="#Ligações_externas"> <div class="vector-toc-text"> <span class="vector-toc-numb">7</span> <span>Ligações externas</span> </div> </a> <ul id="toc-Ligações_externas-sublist" class="vector-toc-list"> </ul> </li> </ul> </div> </div> </nav> </div> </div> <div class="mw-content-container"> <main id="content" class="mw-body"> <header class="mw-body-header vector-page-titlebar"> <nav aria-label="Conteúdo" class="vector-toc-landmark"> <div id="vector-page-titlebar-toc" class="vector-dropdown vector-page-titlebar-toc vector-button-flush-left" > <input type="checkbox" id="vector-page-titlebar-toc-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-vector-page-titlebar-toc" class="vector-dropdown-checkbox " aria-label="Alternar o índice" > <label id="vector-page-titlebar-toc-label" for="vector-page-titlebar-toc-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--icon-only " aria-hidden="true" ><span class="vector-icon mw-ui-icon-listBullet mw-ui-icon-wikimedia-listBullet"></span> <span class="vector-dropdown-label-text">Alternar o índice</span> </label> <div class="vector-dropdown-content"> <div id="vector-page-titlebar-toc-unpinned-container" class="vector-unpinned-container"> </div> </div> </div> </nav> <h1 id="firstHeading" class="firstHeading mw-first-heading"><span class="mw-page-title-main">Massa atómica</span></h1> <div id="p-lang-btn" class="vector-dropdown mw-portlet mw-portlet-lang" > <input type="checkbox" id="p-lang-btn-checkbox" role="button" aria-haspopup="true" data-event-name="ui.dropdown-p-lang-btn" class="vector-dropdown-checkbox mw-interlanguage-selector" aria-label="Ir para um artigo noutra língua. Disponível em 96 línguas" > <label id="p-lang-btn-label" for="p-lang-btn-checkbox" class="vector-dropdown-label cdx-button cdx-button--fake-button cdx-button--fake-button--enabled cdx-button--weight-quiet cdx-button--action-progressive mw-portlet-lang-heading-96" aria-hidden="true" ><span class="vector-icon mw-ui-icon-language-progressive mw-ui-icon-wikimedia-language-progressive"></span> <span class="vector-dropdown-label-text">96 línguas</span> </label> <div class="vector-dropdown-content"> <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li class="interlanguage-link interwiki-af mw-list-item"><a href="https://af.wikipedia.org/wiki/Atoommassa" title="Atoommassa — africanês" lang="af" hreflang="af" data-title="Atoommassa" data-language-autonym="Afrikaans" data-language-local-name="africanês" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Peso_atomico" title="Peso atomico — aragonês" lang="an" hreflang="an" data-title="Peso atomico" data-language-autonym="Aragonés" data-language-local-name="aragonês" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D9%83%D8%AA%D9%84%D8%A9_%D8%B0%D8%B1%D9%8A%D8%A9" title="كتلة ذرية — árabe" lang="ar" hreflang="ar" data-title="كتلة ذرية" data-language-autonym="العربية" data-language-local-name="árabe" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-ary mw-list-item"><a href="https://ary.wikipedia.org/wiki/%D9%83%D8%AA%D9%84%D8%A9_%D8%AF%D8%B1%D9%8A%D8%A9" title="كتلة درية — Moroccan Arabic" lang="ary" hreflang="ary" data-title="كتلة درية" data-language-autonym="الدارجة" data-language-local-name="Moroccan Arabic" class="interlanguage-link-target"><span>الدارجة</span></a></li><li class="interlanguage-link interwiki-ast mw-list-item"><a href="https://ast.wikipedia.org/wiki/Masa_at%C3%B3mica" title="Masa atómica — asturiano" lang="ast" hreflang="ast" data-title="Masa atómica" data-language-autonym="Asturianu" data-language-local-name="asturiano" class="interlanguage-link-target"><span>Asturianu</span></a></li><li class="interlanguage-link interwiki-az mw-list-item"><a href="https://az.wikipedia.org/wiki/Atom_k%C3%BCtl%C9%99si" title="Atom kütləsi — azerbaijano" lang="az" hreflang="az" data-title="Atom kütləsi" data-language-autonym="Azərbaycanca" data-language-local-name="azerbaijano" class="interlanguage-link-target"><span>Azərbaycanca</span></a></li><li class="interlanguage-link interwiki-ba mw-list-item"><a href="https://ba.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC_%D0%BC%D0%B0%D1%81%D1%81%D0%B0%D2%BB%D1%8B" title="Атом массаһы — bashkir" lang="ba" hreflang="ba" data-title="Атом массаһы" data-language-autonym="Башҡортса" data-language-local-name="bashkir" class="interlanguage-link-target"><span>Башҡортса</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC%D0%BD%D0%B0_%D0%BC%D0%B0%D1%81%D0%B0" title="Атомна маса — búlgaro" lang="bg" hreflang="bg" data-title="Атомна маса" data-language-autonym="Български" data-language-local-name="búlgaro" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%AA%E0%A6%BE%E0%A6%B0%E0%A6%AE%E0%A6%BE%E0%A6%A3%E0%A6%AC%E0%A6%BF%E0%A6%95_%E0%A6%AD%E0%A6%B0" title="পারমাণবিক ভর — bengalês" lang="bn" hreflang="bn" data-title="পারমাণবিক ভর" data-language-autonym="বাংলা" data-language-local-name="bengalês" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-br mw-list-item"><a href="https://br.wikipedia.org/wiki/Mas_atomek" title="Mas atomek — bretão" lang="br" hreflang="br" data-title="Mas atomek" data-language-autonym="Brezhoneg" data-language-local-name="bretão" class="interlanguage-link-target"><span>Brezhoneg</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Atomska_masa" title="Atomska masa — bósnio" lang="bs" hreflang="bs" data-title="Atomska masa" data-language-autonym="Bosanski" data-language-local-name="bósnio" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Massa_at%C3%B2mica" title="Massa atòmica — catalão" lang="ca" hreflang="ca" data-title="Massa atòmica" data-language-autonym="Català" data-language-local-name="catalão" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-ckb mw-list-item"><a href="https://ckb.wikipedia.org/wiki/%DA%A9%DB%8E%D8%B4%DB%8C_%D8%A6%DB%95%D8%AA%DB%86%D9%85%DB%8C" title="کێشی ئەتۆمی — curdo central" lang="ckb" hreflang="ckb" data-title="کێشی ئەتۆمی" data-language-autonym="کوردی" data-language-local-name="curdo central" class="interlanguage-link-target"><span>کوردی</span></a></li><li class="interlanguage-link interwiki-da mw-list-item"><a href="https://da.wikipedia.org/wiki/Atommasse" title="Atommasse — dinamarquês" lang="da" hreflang="da" data-title="Atommasse" data-language-autonym="Dansk" data-language-local-name="dinamarquês" class="interlanguage-link-target"><span>Dansk</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Atommasse" title="Atommasse — alemão" lang="de" hreflang="de" data-title="Atommasse" data-language-autonym="Deutsch" data-language-local-name="alemão" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%91%CF%84%CE%BF%CE%BC%CE%B9%CE%BA%CF%8C_%CE%B2%CE%AC%CF%81%CE%BF%CF%82" title="Ατομικό βάρος — grego" lang="el" hreflang="el" data-title="Ατομικό βάρος" data-language-autonym="Ελληνικά" data-language-local-name="grego" class="interlanguage-link-target"><span>Ελληνικά</span></a></li><li class="interlanguage-link interwiki-en mw-list-item"><a href="https://en.wikipedia.org/wiki/Atomic_mass" title="Atomic mass — inglês" lang="en" hreflang="en" data-title="Atomic mass" data-language-autonym="English" data-language-local-name="inglês" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Atomomaso" title="Atomomaso — esperanto" lang="eo" hreflang="eo" data-title="Atomomaso" data-language-autonym="Esperanto" data-language-local-name="esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/Masa_at%C3%B3mica" title="Masa atómica — espanhol" lang="es" hreflang="es" data-title="Masa atómica" data-language-autonym="Español" data-language-local-name="espanhol" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Aatommass" title="Aatommass — estónio" lang="et" hreflang="et" data-title="Aatommass" data-language-autonym="Eesti" data-language-local-name="estónio" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Masa_atomiko" title="Masa atomiko — basco" lang="eu" hreflang="eu" data-title="Masa atomiko" data-language-autonym="Euskara" data-language-local-name="basco" class="interlanguage-link-target"><span>Euskara</span></a></li><li class="interlanguage-link interwiki-fa mw-list-item"><a href="https://fa.wikipedia.org/wiki/%D8%AC%D8%B1%D9%85_%D8%A7%D8%AA%D9%85%DB%8C" title="جرم اتمی — persa" lang="fa" hreflang="fa" data-title="جرم اتمی" data-language-autonym="فارسی" data-language-local-name="persa" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Atomimassa" title="Atomimassa — finlandês" lang="fi" hreflang="fi" data-title="Atomimassa" data-language-autonym="Suomi" data-language-local-name="finlandês" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Masse_atomique" title="Masse atomique — francês" lang="fr" hreflang="fr" data-title="Masse atomique" data-language-autonym="Français" data-language-local-name="francês" class="interlanguage-link-target"><span>Français</span></a></li><li class="interlanguage-link interwiki-fur mw-list-item"><a href="https://fur.wikipedia.org/wiki/Masse_atomiche" title="Masse atomiche — friulano" lang="fur" hreflang="fur" data-title="Masse atomiche" data-language-autonym="Furlan" data-language-local-name="friulano" class="interlanguage-link-target"><span>Furlan</span></a></li><li class="interlanguage-link interwiki-fy mw-list-item"><a href="https://fy.wikipedia.org/wiki/Atoommassa" title="Atoommassa — frísico ocidental" lang="fy" hreflang="fy" data-title="Atoommassa" data-language-autonym="Frysk" data-language-local-name="frísico ocidental" class="interlanguage-link-target"><span>Frysk</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Mais_adamhach" title="Mais adamhach — irlandês" lang="ga" hreflang="ga" data-title="Mais adamhach" data-language-autonym="Gaeilge" data-language-local-name="irlandês" class="interlanguage-link-target"><span>Gaeilge</span></a></li><li class="interlanguage-link interwiki-gl mw-list-item"><a href="https://gl.wikipedia.org/wiki/Masa_at%C3%B3mica" title="Masa atómica — galego" lang="gl" hreflang="gl" data-title="Masa atómica" data-language-autonym="Galego" data-language-local-name="galego" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%9E%D7%A1%D7%94_%D7%90%D7%98%D7%95%D7%9E%D7%99%D7%AA" title="מסה אטומית — hebraico" lang="he" hreflang="he" data-title="מסה אטומית" data-language-autonym="עברית" data-language-local-name="hebraico" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%E0%A4%AA%E0%A4%B0%E0%A4%AE%E0%A4%BE%E0%A4%A3%E0%A5%81_%E0%A4%A6%E0%A5%8D%E0%A4%B0%E0%A4%B5%E0%A5%8D%E0%A4%AF%E0%A4%AE%E0%A4%BE%E0%A4%A8" title="परमाणु द्रव्यमान — hindi" lang="hi" hreflang="hi" data-title="परमाणु द्रव्यमान" data-language-autonym="हिन्दी" data-language-local-name="hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hif mw-list-item"><a href="https://hif.wikipedia.org/wiki/Atomic_mass" title="Atomic mass — Fiji Hindi" lang="hif" hreflang="hif" data-title="Atomic mass" data-language-autonym="Fiji Hindi" data-language-local-name="Fiji Hindi" class="interlanguage-link-target"><span>Fiji Hindi</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Atomska_masa" title="Atomska masa — croata" lang="hr" hreflang="hr" data-title="Atomska masa" data-language-autonym="Hrvatski" data-language-local-name="croata" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/Mas_atomik" title="Mas atomik — haitiano" lang="ht" hreflang="ht" data-title="Mas atomik" data-language-autonym="Kreyòl ayisyen" data-language-local-name="haitiano" class="interlanguage-link-target"><span>Kreyòl ayisyen</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/Atomt%C3%B6meg" title="Atomtömeg — húngaro" lang="hu" hreflang="hu" data-title="Atomtömeg" data-language-autonym="Magyar" data-language-local-name="húngaro" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D4%B1%D5%BF%D5%B8%D5%B4%D5%A1%D5%B5%D5%AB%D5%B6_%D5%A6%D5%A1%D5%B6%D5%A3%D5%BE%D5%A1%D5%AE" title="Ատոմային զանգված — arménio" lang="hy" hreflang="hy" data-title="Ատոմային զանգված" data-language-autonym="Հայերեն" data-language-local-name="arménio" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Massa_atom" title="Massa atom — indonésio" lang="id" hreflang="id" data-title="Massa atom" data-language-autonym="Bahasa Indonesia" data-language-local-name="indonésio" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/At%C3%B3mmassi" title="Atómmassi — islandês" lang="is" hreflang="is" data-title="Atómmassi" data-language-autonym="Íslenska" data-language-local-name="islandês" class="interlanguage-link-target"><span>Íslenska</span></a></li><li class="interlanguage-link interwiki-it mw-list-item"><a href="https://it.wikipedia.org/wiki/Massa_atomica" title="Massa atomica — italiano" lang="it" hreflang="it" data-title="Massa atomica" data-language-autonym="Italiano" data-language-local-name="italiano" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E5%8E%9F%E5%AD%90%E9%87%8F" title="原子量 — japonês" lang="ja" hreflang="ja" data-title="原子量" data-language-autonym="日本語" data-language-local-name="japonês" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-jbo mw-list-item"><a href="https://jbo.wikipedia.org/wiki/na%27orteryratni" title="na'orteryratni — lojban" lang="jbo" hreflang="jbo" data-title="na'orteryratni" data-language-autonym="La .lojban." data-language-local-name="lojban" class="interlanguage-link-target"><span>La .lojban.</span></a></li><li class="interlanguage-link interwiki-jv mw-list-item"><a href="https://jv.wikipedia.org/wiki/Massa_atom" title="Massa atom — javanês" lang="jv" hreflang="jv" data-title="Massa atom" data-language-autonym="Jawa" data-language-local-name="javanês" class="interlanguage-link-target"><span>Jawa</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%90%E1%83%A2%E1%83%9D%E1%83%9B%E1%83%A3%E1%83%A0%E1%83%98_%E1%83%9B%E1%83%90%E1%83%A1%E1%83%90" title="ატომური მასა — georgiano" lang="ka" hreflang="ka" data-title="ატომური მასა" data-language-autonym="ქართული" data-language-local-name="georgiano" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kab mw-list-item"><a href="https://kab.wikipedia.org/wiki/Takura_tabelkamt" title="Takura tabelkamt — kabyle" lang="kab" hreflang="kab" data-title="Takura tabelkamt" data-language-autonym="Taqbaylit" data-language-local-name="kabyle" class="interlanguage-link-target"><span>Taqbaylit</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC%D0%B4%D1%8B%D2%9B_%D0%BC%D0%B0%D1%81%D1%81%D0%B0" title="Атомдық масса — cazaque" lang="kk" hreflang="kk" data-title="Атомдық масса" data-language-autonym="Қазақша" data-language-local-name="cazaque" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%9B%90%EC%9E%90_%EC%A7%88%EB%9F%89" title="원자 질량 — coreano" lang="ko" hreflang="ko" data-title="원자 질량" data-language-autonym="한국어" data-language-local-name="coreano" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-ky mw-list-item"><a href="https://ky.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC%D0%B4%D1%83%D0%BA_%D0%BC%D0%B0%D1%81%D1%81%D0%B0" title="Атомдук масса — quirguiz" lang="ky" hreflang="ky" data-title="Атомдук масса" data-language-autonym="Кыргызча" data-language-local-name="quirguiz" class="interlanguage-link-target"><span>Кыргызча</span></a></li><li class="interlanguage-link interwiki-la mw-list-item"><a href="https://la.wikipedia.org/wiki/Massa_atomica" title="Massa atomica — latim" lang="la" hreflang="la" data-title="Massa atomica" data-language-autonym="Latina" data-language-local-name="latim" class="interlanguage-link-target"><span>Latina</span></a></li><li class="interlanguage-link interwiki-lb mw-list-item"><a href="https://lb.wikipedia.org/wiki/Atommass" title="Atommass — luxemburguês" lang="lb" hreflang="lb" data-title="Atommass" data-language-autonym="Lëtzebuergesch" data-language-local-name="luxemburguês" class="interlanguage-link-target"><span>Lëtzebuergesch</span></a></li><li class="interlanguage-link interwiki-li mw-list-item"><a href="https://li.wikipedia.org/wiki/Atoomgewich" title="Atoomgewich — limburguês" lang="li" hreflang="li" data-title="Atoomgewich" data-language-autonym="Limburgs" data-language-local-name="limburguês" class="interlanguage-link-target"><span>Limburgs</span></a></li><li class="interlanguage-link interwiki-lmo badge-Q17437796 badge-featuredarticle mw-list-item" title="artigo destacado"><a href="https://lmo.wikipedia.org/wiki/Massa_atomica" title="Massa atomica — lombardo" lang="lmo" hreflang="lmo" data-title="Massa atomica" data-language-autonym="Lombard" data-language-local-name="lombardo" class="interlanguage-link-target"><span>Lombard</span></a></li><li class="interlanguage-link interwiki-lt mw-list-item"><a href="https://lt.wikipedia.org/wiki/Atomin%C4%97_mas%C4%97" title="Atominė masė — lituano" lang="lt" hreflang="lt" data-title="Atominė masė" data-language-autonym="Lietuvių" data-language-local-name="lituano" class="interlanguage-link-target"><span>Lietuvių</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Atommasa" title="Atommasa — letão" lang="lv" hreflang="lv" data-title="Atommasa" data-language-autonym="Latviešu" data-language-local-name="letão" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-mk mw-list-item"><a href="https://mk.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC%D1%81%D0%BA%D0%B0_%D0%BC%D0%B0%D1%81%D0%B0" title="Атомска маса — macedónio" lang="mk" hreflang="mk" data-title="Атомска маса" data-language-autonym="Македонски" data-language-local-name="macedónio" class="interlanguage-link-target"><span>Македонски</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC_%D0%BC%D0%B0%D1%81%D1%81" title="Атом масс — mongol" lang="mn" hreflang="mn" data-title="Атом масс" data-language-autonym="Монгол" data-language-local-name="mongol" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-mr mw-list-item"><a href="https://mr.wikipedia.org/wiki/%E0%A4%85%E0%A4%A3%E0%A5%81%E0%A4%AD%E0%A4%BE%E0%A4%B0" title="अणुभार — marata" lang="mr" hreflang="mr" data-title="अणुभार" data-language-autonym="मराठी" data-language-local-name="marata" class="interlanguage-link-target"><span>मराठी</span></a></li><li class="interlanguage-link interwiki-ms mw-list-item"><a href="https://ms.wikipedia.org/wiki/Jisim_atom" title="Jisim atom — malaio" lang="ms" hreflang="ms" data-title="Jisim atom" data-language-autonym="Bahasa Melayu" data-language-local-name="malaio" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-nds mw-list-item"><a href="https://nds.wikipedia.org/wiki/Atommass" title="Atommass — baixo-alemão" lang="nds" hreflang="nds" data-title="Atommass" data-language-autonym="Plattdüütsch" data-language-local-name="baixo-alemão" class="interlanguage-link-target"><span>Plattdüütsch</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Atoommassa" title="Atoommassa — neerlandês" lang="nl" hreflang="nl" data-title="Atoommassa" data-language-autonym="Nederlands" data-language-local-name="neerlandês" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-nn mw-list-item"><a href="https://nn.wikipedia.org/wiki/Atommasse" title="Atommasse — norueguês nynorsk" lang="nn" hreflang="nn" data-title="Atommasse" data-language-autonym="Norsk nynorsk" data-language-local-name="norueguês nynorsk" class="interlanguage-link-target"><span>Norsk nynorsk</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Atommasse" title="Atommasse — norueguês bokmål" lang="nb" hreflang="nb" data-title="Atommasse" data-language-autonym="Norsk bokmål" data-language-local-name="norueguês bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-pa mw-list-item"><a href="https://pa.wikipedia.org/wiki/%E0%A8%AA%E0%A8%B0%E0%A8%AE%E0%A8%BE%E0%A8%A3%E0%A8%B5%E0%A9%80_%E0%A8%AD%E0%A8%BE%E0%A8%B0" title="ਪਰਮਾਣਵੀ ਭਾਰ — panjabi" lang="pa" hreflang="pa" data-title="ਪਰਮਾਣਵੀ ਭਾਰ" data-language-autonym="ਪੰਜਾਬੀ" data-language-local-name="panjabi" class="interlanguage-link-target"><span>ਪੰਜਾਬੀ</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Masa_atomowa" title="Masa atomowa — polaco" lang="pl" hreflang="pl" data-title="Masa atomowa" data-language-autonym="Polski" data-language-local-name="polaco" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pms mw-list-item"><a href="https://pms.wikipedia.org/wiki/Massa_at%C3%B2mica" title="Massa atòmica — Piedmontese" lang="pms" hreflang="pms" data-title="Massa atòmica" data-language-autonym="Piemontèis" data-language-local-name="Piedmontese" class="interlanguage-link-target"><span>Piemontèis</span></a></li><li class="interlanguage-link interwiki-pnb mw-list-item"><a href="https://pnb.wikipedia.org/wiki/%D8%A7%DB%8C%D9%B9%D9%85%DB%8C_%D8%A8%DA%BE%D8%A7%D8%B1" title="ایٹمی بھار — Western Punjabi" lang="pnb" hreflang="pnb" data-title="ایٹمی بھار" data-language-autonym="پنجابی" data-language-local-name="Western Punjabi" class="interlanguage-link-target"><span>پنجابی</span></a></li><li class="interlanguage-link interwiki-qu mw-list-item"><a href="https://qu.wikipedia.org/wiki/I%C3%B1uku_wisnu" title="Iñuku wisnu — quíchua" lang="qu" hreflang="qu" data-title="Iñuku wisnu" data-language-autonym="Runa Simi" data-language-local-name="quíchua" class="interlanguage-link-target"><span>Runa Simi</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Mas%C4%83_atomic%C4%83" title="Masă atomică — romeno" lang="ro" hreflang="ro" data-title="Masă atomică" data-language-autonym="Română" data-language-local-name="romeno" class="interlanguage-link-target"><span>Română</span></a></li><li class="interlanguage-link interwiki-ru mw-list-item"><a href="https://ru.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC%D0%BD%D0%B0%D1%8F_%D0%BC%D0%B0%D1%81%D1%81%D0%B0" title="Атомная масса — russo" lang="ru" hreflang="ru" data-title="Атомная масса" data-language-autonym="Русский" data-language-local-name="russo" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-rue mw-list-item"><a href="https://rue.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC%D0%BE%D0%B2%D0%B0_%D0%BC%D0%B0%D1%81%D0%B0" title="Атомова маса — Rusyn" lang="rue" hreflang="rue" data-title="Атомова маса" data-language-autonym="Русиньскый" data-language-local-name="Rusyn" class="interlanguage-link-target"><span>Русиньскый</span></a></li><li class="interlanguage-link interwiki-sd mw-list-item"><a href="https://sd.wikipedia.org/wiki/%D8%A7%D9%8A%D9%BD%D9%85%D9%8A_%D9%85%D8%A7%D9%8A%D9%88" title="ايٽمي مايو — sindi" lang="sd" hreflang="sd" data-title="ايٽمي مايو" data-language-autonym="سنڌي" data-language-local-name="sindi" class="interlanguage-link-target"><span>سنڌي</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Atomska_masa" title="Atomska masa — servo-croata" lang="sh" hreflang="sh" data-title="Atomska masa" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="servo-croata" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-si mw-list-item"><a href="https://si.wikipedia.org/wiki/%E0%B6%B4%E0%B6%BB%E0%B6%B8%E0%B7%8F%E0%B6%AB%E0%B7%94%E0%B6%9A_%E0%B7%83%E0%B7%8A%E0%B6%9A%E0%B6%B1%E0%B7%8A%E0%B6%B0%E0%B6%BA" title="පරමාණුක ස්කන්ධය — cingalês" lang="si" hreflang="si" data-title="පරමාණුක ස්කන්ධය" data-language-autonym="සිංහල" data-language-local-name="cingalês" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-simple mw-list-item"><a href="https://simple.wikipedia.org/wiki/Atomic_mass" title="Atomic mass — Simple English" lang="en-simple" hreflang="en-simple" data-title="Atomic mass" data-language-autonym="Simple English" data-language-local-name="Simple English" class="interlanguage-link-target"><span>Simple English</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/At%C3%B3mov%C3%A1_hmotnos%C5%A5" title="Atómová hmotnosť — eslovaco" lang="sk" hreflang="sk" data-title="Atómová hmotnosť" data-language-autonym="Slovenčina" data-language-local-name="eslovaco" class="interlanguage-link-target"><span>Slovenčina</span></a></li><li class="interlanguage-link interwiki-sl mw-list-item"><a href="https://sl.wikipedia.org/wiki/Atomska_te%C5%BEa" title="Atomska teža — esloveno" lang="sl" hreflang="sl" data-title="Atomska teža" data-language-autonym="Slovenščina" data-language-local-name="esloveno" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-so mw-list-item"><a href="https://so.wikipedia.org/wiki/Cuf_atam" title="Cuf atam — somali" lang="so" hreflang="so" data-title="Cuf atam" data-language-autonym="Soomaaliga" data-language-local-name="somali" class="interlanguage-link-target"><span>Soomaaliga</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Masa_atomike" title="Masa atomike — albanês" lang="sq" hreflang="sq" data-title="Masa atomike" data-language-autonym="Shqip" data-language-local-name="albanês" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/Atomska_masa" title="Atomska masa — sérvio" lang="sr" hreflang="sr" data-title="Atomska masa" data-language-autonym="Српски / srpski" data-language-local-name="sérvio" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-stq mw-list-item"><a href="https://stq.wikipedia.org/wiki/Atommasse" title="Atommasse — Saterland Frisian" lang="stq" hreflang="stq" data-title="Atommasse" data-language-autonym="Seeltersk" data-language-local-name="Saterland Frisian" class="interlanguage-link-target"><span>Seeltersk</span></a></li><li class="interlanguage-link interwiki-su mw-list-item"><a href="https://su.wikipedia.org/wiki/Massa_atom" title="Massa atom — sundanês" lang="su" hreflang="su" data-title="Massa atom" data-language-autonym="Sunda" data-language-local-name="sundanês" class="interlanguage-link-target"><span>Sunda</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Atommassa" title="Atommassa — sueco" lang="sv" hreflang="sv" data-title="Atommassa" data-language-autonym="Svenska" data-language-local-name="sueco" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-sw mw-list-item"><a href="https://sw.wikipedia.org/wiki/Uzani_atomia" title="Uzani atomia — suaíli" lang="sw" hreflang="sw" data-title="Uzani atomia" data-language-autonym="Kiswahili" data-language-local-name="suaíli" class="interlanguage-link-target"><span>Kiswahili</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%85%E0%AE%A3%E0%AF%81_%E0%AE%A8%E0%AE%BF%E0%AE%B1%E0%AF%88" title="அணு நிறை — tâmil" lang="ta" hreflang="ta" data-title="அணு நிறை" data-language-autonym="தமிழ்" data-language-local-name="tâmil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-tg mw-list-item"><a href="https://tg.wikipedia.org/wiki/%D0%9C%D0%B0%D1%81%D1%81%D0%B0%D0%B8_%D0%B0%D1%82%D0%BE%D0%BC%D3%A3" title="Массаи атомӣ — tajique" lang="tg" hreflang="tg" data-title="Массаи атомӣ" data-language-autonym="Тоҷикӣ" data-language-local-name="tajique" class="interlanguage-link-target"><span>Тоҷикӣ</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B8%A1%E0%B8%A7%E0%B8%A5%E0%B8%AD%E0%B8%B0%E0%B8%95%E0%B8%AD%E0%B8%A1" title="มวลอะตอม — tailandês" lang="th" hreflang="th" data-title="มวลอะตอม" data-language-autonym="ไทย" data-language-local-name="tailandês" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tl mw-list-item"><a href="https://tl.wikipedia.org/wiki/Atomikong_masa" title="Atomikong masa — tagalo" lang="tl" hreflang="tl" data-title="Atomikong masa" data-language-autonym="Tagalog" data-language-local-name="tagalo" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/Atom_k%C3%BCtlesi" title="Atom kütlesi — turco" lang="tr" hreflang="tr" data-title="Atom kütlesi" data-language-autonym="Türkçe" data-language-local-name="turco" class="interlanguage-link-target"><span>Türkçe</span></a></li><li class="interlanguage-link interwiki-uk mw-list-item"><a href="https://uk.wikipedia.org/wiki/%D0%90%D1%82%D0%BE%D0%BC%D0%BD%D0%B0_%D0%BC%D0%B0%D1%81%D0%B0" title="Атомна маса — ucraniano" lang="uk" hreflang="uk" data-title="Атомна маса" data-language-autonym="Українська" data-language-local-name="ucraniano" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-ur mw-list-item"><a href="https://ur.wikipedia.org/wiki/%D8%AC%D9%88%DB%81%D8%B1%DB%8C_%DA%A9%D9%85%DB%8C%D8%AA" title="جوہری کمیت — urdu" lang="ur" hreflang="ur" data-title="جوہری کمیت" data-language-autonym="اردو" data-language-local-name="urdu" class="interlanguage-link-target"><span>اردو</span></a></li><li class="interlanguage-link interwiki-uz mw-list-item"><a href="https://uz.wikipedia.org/wiki/Atom_massasi" title="Atom massasi — usbeque" lang="uz" hreflang="uz" data-title="Atom massasi" data-language-autonym="Oʻzbekcha / ўзбекча" data-language-local-name="usbeque" class="interlanguage-link-target"><span>Oʻzbekcha / ўзбекча</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/Nguy%C3%AAn_t%E1%BB%AD_kh%E1%BB%91i" title="Nguyên tử khối — vietnamita" lang="vi" hreflang="vi" data-title="Nguyên tử khối" data-language-autonym="Tiếng Việt" data-language-local-name="vietnamita" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-war mw-list-item"><a href="https://war.wikipedia.org/wiki/Masa_atomika" title="Masa atomika — waray" lang="war" hreflang="war" data-title="Masa atomika" data-language-autonym="Winaray" data-language-local-name="waray" class="interlanguage-link-target"><span>Winaray</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E5%8E%9F%E5%AD%90%E9%87%8F" title="原子量 — wu" lang="wuu" hreflang="wuu" data-title="原子量" data-language-autonym="吴语" data-language-local-name="wu" class="interlanguage-link-target"><span>吴语</span></a></li><li class="interlanguage-link interwiki-yo mw-list-item"><a href="https://yo.wikipedia.org/wiki/%C3%8Cw%C3%BAwo_%C3%A1t%E1%BB%8D%CC%80m%C3%B9" title="Ìwúwo átọ̀mù — ioruba" lang="yo" hreflang="yo" data-title="Ìwúwo átọ̀mù" data-language-autonym="Yorùbá" data-language-local-name="ioruba" class="interlanguage-link-target"><span>Yorùbá</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E5%8E%9F%E5%AD%90%E9%87%8F" title="原子量 — chinês" lang="zh" hreflang="zh" data-title="原子量" data-language-autonym="中文" data-language-local-name="chinês" class="interlanguage-link-target"><span>中文</span></a></li><li class="interlanguage-link interwiki-zh-min-nan mw-list-item"><a href="https://zh-min-nan.wikipedia.org/wiki/Go%C3%A2n-ch%C3%BA_chit-li%C5%8Dng" title="Goân-chú chit-liōng — min nan" lang="nan" hreflang="nan" data-title="Goân-chú chit-liōng" data-language-autonym="閩南語 / Bân-lâm-gú" data-language-local-name="min nan" class="interlanguage-link-target"><span>閩南語 / Bân-lâm-gú</span></a></li><li class="interlanguage-link interwiki-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E5%8E%9F%E5%AD%90%E8%B3%AA%E9%87%8F" title="原子質量 — cantonês" lang="yue" hreflang="yue" data-title="原子質量" data-language-autonym="粵語" data-language-local-name="cantonês" class="interlanguage-link-target"><span>粵語</span></a></li> </ul> <div class="after-portlet after-portlet-lang"><span class="wb-langlinks-edit wb-langlinks-link"><a href="https://www.wikidata.org/wiki/Special:EntityPage/Q3840065#sitelinks-wikipedia" title="Editar hiperligações interlínguas" class="wbc-editpage">Editar hiperligações</a></span></div> </div> </div> </div> </header> <div class="vector-page-toolbar"> <div class="vector-page-toolbar-container"> <div id="left-navigation"> <nav aria-label="Espaços nominais"> <div id="p-associated-pages" class="vector-menu vector-menu-tabs mw-portlet mw-portlet-associated-pages" > <div class="vector-menu-content"> <ul class="vector-menu-content-list"> <li id="ca-nstab-main" class="selected vector-tab-noicon mw-list-item"><a href="/wiki/Massa_at%C3%B3mica" title="Ver a página de conteúdo [c]" 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0;border-collapse:collapse;border:1px solid #c0c090;background-color:#f8eaba;box-sizing:border-box}.mw-parser-output .tmbox.mbox-small{font-size:88%;line-height:1.25em}.mw-parser-output .tmbox-speedy{border:2px solid #b32424;background-color:#fee7e6}.mw-parser-output .tmbox-delete{border:2px solid #b32424}.mw-parser-output .tmbox-content{border:1px solid #c0c090}.mw-parser-output .tmbox-style{border:2px solid #fc3}.mw-parser-output .tmbox-move{border:2px solid #9932cc}.mw-parser-output .tmbox .mbox-text{border:none;padding:0.25em 0.9em;width:100%}.mw-parser-output .tmbox .mbox-image{border:none;padding:2px 0 2px 0.9em;text-align:center}.mw-parser-output .tmbox .mbox-imageright{border:none;padding:2px 0.9em 2px 0;text-align:center}.mw-parser-output .tmbox .mbox-empty-cell{border:none;padding:0;width:1px}.mw-parser-output .tmbox .mbox-invalid-type{text-align:center}@media(min-width:720px){.mw-parser-output .tmbox{margin:4px 10%}.mw-parser-output .tmbox.mbox-small{clear:right;float:right;margin:4px 0 4px 1em;width:238px}}@media screen{html.skin-theme-clientpref-night .mw-parser-output .tmbox{background-color:#2e2505}html.skin-theme-clientpref-night .mw-parser-output .tmbox-speedy{background-color:#310402}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .tmbox{background-color:#2e2505}html.skin-theme-clientpref-os .mw-parser-output .tmbox-speedy{background-color:#310402}}body.skin--responsive .mw-parser-output table.tmbox img{max-width:none!important}</style><table class="box-Revisão plainlinks metadata ambox ambox-content ambox-content" role="presentation"><tbody><tr><td class="mbox-image"><div style="width:52px"><span typeof="mw:File"><a href="/wiki/Ficheiro:Searchtool.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/61/Searchtool.svg/40px-Searchtool.svg.png" decoding="async" width="40" height="40" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/61/Searchtool.svg/60px-Searchtool.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/61/Searchtool.svg/80px-Searchtool.svg.png 2x" data-file-width="512" data-file-height="512" /></a></span></div></td><td class="mbox-text"><div class="mbox-text-span"><b>Esta página ou seção foi marcada para revisão devido a incoerências ou dados de confiabilidade duvidosa.</b><span class="hide-when-compact"> Se tem algum conhecimento sobre o tema, por favor, verifique e <span class="plainlinks"><a class="external text" href="https://pt.wikipedia.org/w/index.php?title=Massa_at%C3%B3mica&action=edit">melhore</a></span> a coerência e o rigor deste artigo.<br /><small>Considere colocar uma explicação mais detalhada na <a href="/wiki/Discuss%C3%A3o:Massa_at%C3%B3mica" title="Discussão:Massa atómica">discussão</a>.</small></span> <small class="date-container"><i>(<span class="date">Março de 2011</span>)</i></small></div></td></tr></tbody></table> <figure class="mw-halign-right" typeof="mw:File/Thumb"><a href="/wiki/Ficheiro:Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg" class="mw-file-description"><img src="//upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/200px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png" decoding="async" width="200" height="226" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/300px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/6/6f/Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg/400px-Stylised_atom_with_three_Bohr_model_orbits_and_stylised_nucleus.svg.png 2x" data-file-width="530" data-file-height="600" /></a><figcaption>Representação de um átomo de <a href="/wiki/L%C3%ADtio" title="Lítio">lítio</a>-7 em seu estado fundamental: 3 prótons, 4 nêutrons e 3 elétrons. Os elétrons representados estão fora de escala, possuindo um tamanho aproximado de 1/1800 de um próton/nêutron).</figcaption></figure> <p><span class="no-conversion"><b><span lang="pt-pt">Massa atómica</span></b> <sup>(<a href="/wiki/Portugu%C3%AAs_europeu" title="Português europeu">português europeu</a>)</sup> ou <b><span lang="pt-br">massa atômica</span></b> <sup>(<a href="/wiki/Portugu%C3%AAs_brasileiro" title="Português brasileiro">português brasileiro</a>)</sup></span> é a <a href="/wiki/M%C3%A9dia" title="Média">média</a> dos números de massa molecular (representada pela letra A) do <a href="/wiki/Is%C3%B3topos" class="mw-redirect" title="Isótopos">isótopos</a> de um determinado <a href="/wiki/Elemento_qu%C3%ADmico" class="mw-redirect" title="Elemento químico">elemento químico</a>, <a href="/wiki/M%C3%A9dia_ponderada" class="mw-redirect" title="Média ponderada">ponderada</a> pela ocorrência de cada isótopo. Número de massa (<b>A</b>) é a soma de <a href="/wiki/Pr%C3%B3tons" class="mw-redirect" title="Prótons">prótons</a> e <a href="/wiki/N%C3%AAutrons" class="mw-redirect" title="Nêutrons">nêutrons</a> do núcleo de um <a href="/wiki/%C3%81tomo" title="Átomo">átomo</a>, medida em <a href="/wiki/Unidade_de_massa_at%C3%B3mica" class="mw-redirect" title="Unidade de massa atómica">unidade de massa atómica</a>, representado por <b>u.m.a</b> ou simplesmente <b>u.</b> </p> <meta property="mw:PageProp/toc" /> <div class="mw-heading mw-heading2"><h2 id="Definição"><span id="Defini.C3.A7.C3.A3o"></span>Definição</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massa_at%C3%B3mica&veaction=edit&section=1" title="Editar secção: Definição" class="mw-editsection-visualeditor"><span>editar</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Massa_at%C3%B3mica&action=edit&section=1" title="Editar código-fonte da secção: Definição"><span>editar código-fonte</span></a><span class="mw-editsection-bracket">]</span></span></div> <table class="cquote" role="presentation" style="margin:auto; border-collapse: collapse; border: none; color: inherit; background-color: transparent; width: auto;"> <tbody><tr> <td style="width: 20px; vertical-align: top; border: none; color: #B2B7F2; font-size: 40px; font-family: 'Times New Roman', Times, serif; font-weight: bold; line-height: .6em; text-align: left; padding: 10px 10px;">“ </td> <td style="vertical-align: top; border: none; padding: 4px 10px;">A massa atómica de um elemento químico é a média das massas atómicas dos isótopos desse elemento químico, ponderada pela ocorrência dos variados isótopos. </td> <td style="width: 20px; vertical-align: bottom; border: none; color: #B2B7F2; font-size: 40px; font-family: 'Times New Roman', Times, serif; font-weight: bold; line-height: .6em; text-align: right; padding: 10px 10px;">” </td></tr> </tbody></table> <center><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle m.a.={\frac {\sum (\mathrm {\%\ de\ ocorr{\hat {e}}ncia} \times {\text{massa atomica}})}{100}}}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>m</mi> <mo>.</mo> <mi>a</mi> <mo>.</mo> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo>∑</mo> <mo stretchy="false">(</mo> <mrow class="MJX-TeXAtom-ORD"> <mi mathvariant="normal">%</mi> <mtext> </mtext> <mi mathvariant="normal">d</mi> <mi mathvariant="normal">e</mi> <mtext> </mtext> <mi mathvariant="normal">o</mi> <mi mathvariant="normal">c</mi> <mi mathvariant="normal">o</mi> <mi mathvariant="normal">r</mi> <mi mathvariant="normal">r</mi> <mrow class="MJX-TeXAtom-ORD"> <mrow class="MJX-TeXAtom-ORD"> <mover> <mi mathvariant="normal">e</mi> <mo stretchy="false">^</mo> </mover> </mrow> </mrow> <mi mathvariant="normal">n</mi> <mi mathvariant="normal">c</mi> <mi mathvariant="normal">i</mi> <mi mathvariant="normal">a</mi> </mrow> <mo>×</mo> <mrow class="MJX-TeXAtom-ORD"> <mtext>massa atomica</mtext> </mrow> <mo stretchy="false">)</mo> </mrow> <mn>100</mn> </mfrac> </mrow> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle m.a.={\frac {\sum (\mathrm {\%\ de\ ocorr{\hat {e}}ncia} \times {\text{massa atomica}})}{100}}}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/d7e7893c421d5a0fa01f1714f8c0c4d06a1a5fc3" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:46.311ex; height:5.676ex;" alt="{\displaystyle m.a.={\frac {\sum (\mathrm {\%\ de\ ocorr{\hat {e}}ncia} \times {\text{massa atomica}})}{100}}}"></span></center> <p>Por exemplo há dois isótopos conhecidos do Cloro, sendo eles o Cloro-35 e o Cloro-37. O primeiro, com massa atómica de 34,9689 u tem uma ocorrência na natureza em torno de 75,77%, enquanto que o outro isótopo, de massa 36,96590 u, tem uma ocorrência de 24,23%. Dito de outra forma, qualquer amostra de átomos de Cloro será átomos de Cloro-37. Sendo assim, a massa atómica do elemento Cloro é </p> <center><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle m.a._{Cl}={\frac {(75,77\times 34,9689u)+(24,23\times 36,96590u)}{100}}=35,45u}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mi>m</mi> <mo>.</mo> <mi>a</mi> <msub> <mo>.</mo> <mrow class="MJX-TeXAtom-ORD"> <mi>C</mi> <mi>l</mi> </mrow> </msub> <mo>=</mo> <mrow class="MJX-TeXAtom-ORD"> <mfrac> <mrow> <mo stretchy="false">(</mo> <mn>75</mn> <mo>,</mo> <mn>77</mn> <mo>×</mo> <mn>34</mn> <mo>,</mo> <mn>9689</mn> <mi>u</mi> <mo stretchy="false">)</mo> <mo>+</mo> <mo stretchy="false">(</mo> <mn>24</mn> <mo>,</mo> <mn>23</mn> <mo>×</mo> <mn>36</mn> <mo>,</mo> <mn>96590</mn> <mi>u</mi> <mo stretchy="false">)</mo> </mrow> <mn>100</mn> </mfrac> </mrow> <mo>=</mo> <mn>35</mn> <mo>,</mo> <mn>45</mn> <mi>u</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle m.a._{Cl}={\frac {(75,77\times 34,9689u)+(24,23\times 36,96590u)}{100}}=35,45u}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/fedeb397a2e22d044aed7235b14e4c91621d48e2" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -1.838ex; width:64.057ex; height:5.676ex;" alt="{\displaystyle m.a._{Cl}={\frac {(75,77\times 34,9689u)+(24,23\times 36,96590u)}{100}}=35,45u}"></span></center> <p>Conforme exposto acima, levando em consideração a ocorrência na natureza, sabe-se que a massa atómica do elemento Cloro é de 35,45 u. </p><p>Pela definição de "u" (unidade de massa atómica) corresponde a 1/12 da massa do <a href="/wiki/Carbono-12" title="Carbono-12">Carbono-12</a>. Como a massa atómica é expressa em "u", ela indica quantas vezes a massa de um átomo é maior que 1/12 da massa de Carbono-12. </p><p>Por exemplo referir que a massa atómica de um dado isótopo do flúor é 19 <a href="/wiki/Unidade_de_massa_at%C3%B3mica" class="mw-redirect" title="Unidade de massa atómica">u</a>, indica que o isótopo em questão é 19 vezes "mais pesado" que 1/12 da massa do <a href="/wiki/Carbono-12" title="Carbono-12">carbono-12</a>. </p> <div class="mw-heading mw-heading2"><h2 id="Massa_molecular">Massa molecular</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massa_at%C3%B3mica&veaction=edit&section=2" title="Editar secção: Massa molecular" class="mw-editsection-visualeditor"><span>editar</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Massa_at%C3%B3mica&action=edit&section=2" title="Editar código-fonte da secção: Massa molecular"><span>editar código-fonte</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>Uma definição semelhante aplica-se às <a href="/wiki/Mol%C3%A9cula" title="Molécula">moléculas</a> - sendo então chamada <a href="/wiki/Massa_molecular" title="Massa molecular">massa molecular</a> de uma <a href="/wiki/Subst%C3%A2ncia" title="Substância">substância</a>, expressa em "u". </p><p>A massa da molécula de uma dada substância é calculada pela soma das massas atómicas de todos os seus átomos constituintes. Esta técnica deixa de lado apenas a <a href="/wiki/Energia_de_liga%C3%A7%C3%A3o" title="Energia de ligação">energia de ligação</a> química, que geralmente é negligenciável. </p><p>Por exemplo, a molécula de <a href="/wiki/Metano" title="Metano">metano</a> é composta por 1 átomo de <a href="/wiki/Carbono" title="Carbono">carbono</a> e 4 átomos de <a href="/wiki/Hidrog%C3%A9nio" title="Hidrogénio">hidrogénio</a>. Sabendo que a massa atómica do hidrogénio é aproximadamente 1 u e a do carbono aproximadamente 12 u, então a massa atómica da substância metano (massa de uma molécula de metano) é calculada da seguinte forma: </p><p><span class="mwe-math-element"><span class="mwe-math-mathml-inline mwe-math-mathml-a11y" style="display: none;"><math xmlns="http://www.w3.org/1998/Math/MathML" alttext="{\displaystyle (4\times 1u)+(1\times 12u)=16u}"> <semantics> <mrow class="MJX-TeXAtom-ORD"> <mstyle displaystyle="true" scriptlevel="0"> <mo stretchy="false">(</mo> <mn>4</mn> <mo>×</mo> <mn>1</mn> <mi>u</mi> <mo stretchy="false">)</mo> <mo>+</mo> <mo stretchy="false">(</mo> <mn>1</mn> <mo>×</mo> <mn>12</mn> <mi>u</mi> <mo stretchy="false">)</mo> <mo>=</mo> <mn>16</mn> <mi>u</mi> </mstyle> </mrow> <annotation encoding="application/x-tex">{\displaystyle (4\times 1u)+(1\times 12u)=16u}</annotation> </semantics> </math></span><img src="https://wikimedia.org/api/rest_v1/media/math/render/svg/414072bb8bcd480c98fb7f77d1e1cfd16846d672" class="mwe-math-fallback-image-inline mw-invert skin-invert" aria-hidden="true" style="vertical-align: -0.838ex; width:27.364ex; height:2.843ex;" alt="{\displaystyle (4\times 1u)+(1\times 12u)=16u}"></span> </p> <div class="mw-heading mw-heading2"><h2 id="Escrita">Escrita</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massa_at%C3%B3mica&veaction=edit&section=3" title="Editar secção: Escrita" class="mw-editsection-visualeditor"><span>editar</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Massa_at%C3%B3mica&action=edit&section=3" title="Editar código-fonte da secção: Escrita"><span>editar código-fonte</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A massa atômica relativa de um elemento "E" pode ser escrita como <b><i>A</i><sub>r</sub>°(E)</b> ou <b><i>A</i><sub>r</sub>(E)</b>. Assim, <i>A</i><sub>r</sub>(<a href="/wiki/Carbono" title="Carbono">C</a>) = 12. </p><p>A massa atômica pode ser apresentada de maneira arredondada, apresentando a <a href="/wiki/Incerteza_de_medi%C3%A7%C3%A3o" title="Incerteza de medição">incerteza de medição</a>, ou ainda como intervalo.<sup id="cite_ref-rocha_1-0" class="reference"><a href="#cite_note-rocha-1"><span>[</span>1<span>]</span></a></sup> </p><p>Cada elemento pode ter sua massa arredondada, chamado peso atômico convencional. A do Hidrogênio é 1,008.<sup id="cite_ref-rocha_1-1" class="reference"><a href="#cite_note-rocha-1"><span>[</span>1<span>]</span></a></sup> </p><p>No entanto, pode-se expressas esse valor com sua incerteza, como 1,007 94(7), indicando uma variação entre 1,007 87 até 1,008 01.<sup id="cite_ref-rocha_1-2" class="reference"><a href="#cite_note-rocha-1"><span>[</span>1<span>]</span></a></sup> Também utiliza-se a notação com <a href="/wiki/%C2%B1" class="mw-redirect" title="±">±</a>, podendo a mesma informação ser escrita 1,007 94 ± 0,000 07. </p><p>A massa também pode ser expressa em um intervalo, para elementos cuja massa varie muito na natureza. Assim, a massa do Hidrogênio passou a ser expressa como [1,007 84; 1,008 11], com valores além do esperado. Assim, espera-se que qualquer medida de Hidrogênio esteja entre esses intervalos.<sup id="cite_ref-rocha_1-3" class="reference"><a href="#cite_note-rocha-1"><span>[</span>1<span>]</span></a></sup> </p><p>Para elementos sintetizados em laboratório, que possuem meia-vida muito curta, apresenta-se a massa atômica do isótopo mais comum entre parêntesis. Assim, <i>A</i><sub>r</sub>(<a href="/wiki/Copern%C3%ADcio" title="Copernício">Cp</a>) = (285). </p> <div class="mw-heading mw-heading2"><h2 id="Desenvolvimento_histórico_do_termo"><span id="Desenvolvimento_hist.C3.B3rico_do_termo"></span>Desenvolvimento histórico do termo</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massa_at%C3%B3mica&veaction=edit&section=4" title="Editar secção: Desenvolvimento histórico do termo" class="mw-editsection-visualeditor"><span>editar</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Massa_at%C3%B3mica&action=edit&section=4" title="Editar código-fonte da secção: Desenvolvimento histórico do termo"><span>editar código-fonte</span></a><span class="mw-editsection-bracket">]</span></span></div> <p>A noção de massa atómica foi referida pela primeira vez por <a href="/wiki/John_Dalton" title="John Dalton">John Dalton</a>, em sequência da <a href="/wiki/Teoria_at%C3%B3mica" class="mw-redirect" title="Teoria atómica">teoria atómica</a> que desenvolveu. Como Dalton não tinha forma de calcular a massa de um átomo tinha de relacionar a massa de átomos de diferentes elementos entre si. Para tal era necessário escolher os átomos de um elemento específico como referência. Dalton escolheu como elemento referência o hidrogénio. </p><p>Dalton efetuou cálculos de massa atómica para vários elementos, tendo com ponto de referência a massa do hidrogénio, que ele estabeleceu ser a unidade (1). No entanto estes cálculos eram empíricos, baseados exclusivamente na <a href="/wiki/F%C3%B3rmula_qu%C3%ADmica" title="Fórmula química">fórmula química</a> das substâncias, mas não em experiências concretas. Este facto levou à conclusões erradas. Por exemplo. Dalton considerava que uma molécula de <a href="/wiki/%C3%81gua" title="Água">água</a> era constituída por um átomo de hidrogénio e um átomo de oxigénio (HO). Considerando a massa atómica do hidrogénio(H) igual a 1, a massa do oxigénio(O) seria 8. No entanto a massa atómica relativa do oxigénio é 16 (porque uma molécula de água possui 2 átomos de hidrogénio e 1 de oxigénio). </p><p>No início do <a href="/wiki/S%C3%A9culo_XIX" title="Século XIX">século XIX</a> o químico sueco <a href="/wiki/J%C3%B6ns_Jacob_Berzelius" title="Jöns Jacob Berzelius">Berzellius</a> efetuou várias experiências para determinar a massa atómica dos elementos conhecidos na época. Berzellius utilizou como elemento de comparação a massa atómica do Oxigénio, que igualou a 100 e em 1828 publicou uma tabela que apresentava a massa atómica de vários <a href="/wiki/Elemento_qu%C3%ADmico" class="mw-redirect" title="Elemento químico">elementos químicos</a>. Em 1865 o químico belga J. S. Stas apresentou uma tabela de massas atómicas mais actualizada, utilizando como comparação o elemento oxigénio, que igualou a 16. </p><p>Mais tarde passaram a existir dois elementos referência para a determinação da massa atômica dos elementos, o oxigénio (igualado a 16 unidades) e o carbono (igualado a 12 unidades). Este fato causou considerável confusão. Em 1961 foi universalmente aceito o carbono (igualado a 12 unidades). </p> <div class="mw-heading mw-heading2"><h2 id="Ver_também"><span id="Ver_tamb.C3.A9m"></span>Ver também</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massa_at%C3%B3mica&veaction=edit&section=5" title="Editar secção: Ver também" class="mw-editsection-visualeditor"><span>editar</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Massa_at%C3%B3mica&action=edit&section=5" title="Editar código-fonte da secção: Ver também"><span>editar código-fonte</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><a href="/wiki/Massa" title="Massa">Massa</a></li> <li><a href="/wiki/Massa_molar" title="Massa molar">Massa molar</a></li> <li><a href="/wiki/Massa_molecular" title="Massa molecular">Massa molecular</a></li> <li><a href="/wiki/Unidade_de_massa_at%C3%B4mica" title="Unidade de massa atômica">Unidade de massa atômica</a></li></ul> <div class="mw-heading mw-heading2"><h2 id="Bibliografia">Bibliografia</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massa_at%C3%B3mica&veaction=edit&section=6" title="Editar secção: Bibliografia" class="mw-editsection-visualeditor"><span>editar</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Massa_at%C3%B3mica&action=edit&section=6" title="Editar código-fonte da secção: Bibliografia"><span>editar código-fonte</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><cite class="citation book">Asimov, Isaac (2004). <i>Átomo</i>. Lisboa: Campos das Letras</cite><span title="ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fpt.wikipedia.org%3AMassa+at%C3%B3mica&rft.au=Asimov%2C+Isaac&rft.btitle=%C3%81tomo&rft.date=2004&rft.genre=book&rft.place=Lisboa&rft.pub=Campos+das+Letras&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook" class="Z3988"><span style="display:none;"> </span></span></li> <li><cite class="citation book">Pauling, Linus (1988). <i>General Chemistry</i>. New York: Dover Publications</cite><span title="ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fpt.wikipedia.org%3AMassa+at%C3%B3mica&rft.au=Pauling%2C+Linus&rft.btitle=General+Chemistry&rft.date=1988&rft.genre=book&rft.place=New+York&rft.pub=Dover+Publications&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook" class="Z3988"><span style="display:none;"> </span></span></li> <li><cite class="citation book">Fonseca, MRM (2004). <i>Química Integral</i>. São Paulo: FTD</cite><span title="ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fpt.wikipedia.org%3AMassa+at%C3%B3mica&rft.au=Fonseca%2C+MRM&rft.btitle=Qu%C3mica+Integral&rft.date=2004&rft.genre=book&rft.place=S%C3%A3o+Paulo&rft.pub=FTD&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook" class="Z3988"><span style="display:none;"> </span></span></li></ul> <div class="mw-heading mw-heading2"><h2 id="Ligações_externas"><span id="Liga.C3.A7.C3.B5es_externas"></span>Ligações externas</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Massa_at%C3%B3mica&veaction=edit&section=7" title="Editar secção: Ligações externas" class="mw-editsection-visualeditor"><span>editar</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Massa_at%C3%B3mica&action=edit&section=7" title="Editar código-fonte da secção: Ligações externas"><span>editar código-fonte</span></a><span class="mw-editsection-bracket">]</span></span></div> <ul><li><cite class="citation web"><a rel="nofollow" class="external text" href="http://physics.nist.gov/cgi-bin/Compositions/stand_alone.pl?ele=&ascii=html&isotype=some">«Massas atômicas de todos os isótopos»</a> (em inglês)</cite><span title="ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fpt.wikipedia.org%3AMassa+at%C3%B3mica&rft.btitle=Massas+at%C3%B4micas+de+todos+os+is%C3%B3topos&rft.genre=unknown&rft_id=http%3A%2F%2Fphysics.nist.gov%2Fcgi-bin%2FCompositions%2Fstand_alone.pl%3Fele%3D%26ascii%3Dhtml%26isotype%3Dsome&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook" class="Z3988"><span style="display:none;"> </span></span></li> <li><cite class="citation web"><a rel="nofollow" class="external text" href="http://www.iupac.org/goldbook/A00496.pdf">«IUPAC goldbook definição de massa atômica»</a> <span style="font-size:85%;">(PDF)</span> (em inglês)</cite><span title="ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fpt.wikipedia.org%3AMassa+at%C3%B3mica&rft.btitle=IUPAC+goldbook+defini%C3%A7%C3%A3o+de+massa+at%C3%B4mica&rft.genre=unknown&rft_id=http%3A%2F%2Fwww.iupac.org%2Fgoldbook%2FA00496.pdf&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook" class="Z3988"><span style="display:none;"> </span></span></li></ul> <ul class="noprint navigation-box" style="border-top: solid silver 1px; border-right: solid silver 1px; border-bottom:1px solid silver; border-left: solid silver 1px; padding:3px; background-color: #F9F9F9; text-align: center; margin-top:10px; margin-left: 0; clear: both;"><li style="display: inline;"><span style="white-space: nowrap; margin: auto 1.5em"><span style="margin-right: 0.5em"><span typeof="mw:File"><a href="/wiki/Ficheiro:Sciences_exactes.svg" title="Portal da química"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/3/37/Sciences_exactes.svg/25px-Sciences_exactes.svg.png" decoding="async" width="25" height="25" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/3/37/Sciences_exactes.svg/38px-Sciences_exactes.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/3/37/Sciences_exactes.svg/50px-Sciences_exactes.svg.png 2x" data-file-width="256" data-file-height="256" /></a></span></span> <span style="font-weight:bold"><a href="/wiki/Portal:Qu%C3%ADmica" title="Portal:Química">Portal da química</a></span></span></li> </ul> <div class="mw-references-wrap"><ol class="references"> <li id="cite_note-rocha-1"><span class="mw-cite-backlink">↑ <sup><i><b><a href="#cite_ref-rocha_1-0">a</a></b></i></sup> <sup><i><b><a href="#cite_ref-rocha_1-1">b</a></b></i></sup> <sup><i><b><a href="#cite_ref-rocha_1-2">c</a></b></i></sup> <sup><i><b><a href="#cite_ref-rocha_1-3">d</a></b></i></sup></span> <span class="reference-text"><cite class="citation web">Rocha-Filho, Romeu C.; Chagas, Aécio Pereira (1 de novembro de 2011). <a rel="nofollow" class="external text" href="http://qnesc.sbq.org.br/online/qnesc33_4/211-AQ-9011.pdf">«Os Pesos Atômicos Deixam de Ser Constantes: Dez Elementos Passam a Ter Intervalos de Pesos Atômicos»</a> <span style="font-size:85%;">(PDF)</span>. <i>QUÍMICA NOVA NA ESCOLA</i><span class="reference-accessdate">. Consultado em 19 de junho de 2024</span></cite><span title="ctx_ver=Z39.88-2004&rfr_id=info%3Asid%2Fpt.wikipedia.org%3AMassa+at%C3%B3mica&rft.atitle=Os+Pesos+At%C3%B4micos+Deixam+de+Ser+Constantes%3A+Dez+Elementos+Passam+a+Ter+Intervalos+de+Pesos+At%C3%B4micos&rft.au=Chagas%2C+A%C3%A9cio+Pereira&rft.aufirst=Romeu+C.&rft.aulast=Rocha-Filho&rft.date=2011-11-01&rft.genre=unknown&rft.jtitle=QU%C3MICA+NOVA+NA+ESCOLA&rft_id=http%3A%2F%2Fqnesc.sbq.org.br%2Fonline%2Fqnesc33_4%2F211-AQ-9011.pdf&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Ajournal" class="Z3988"><span style="display:none;"> </span></span></span> </li> </ol></div>    </div><noscript><img src="https://login.wikimedia.org/wiki/Special:CentralAutoLogin/start?type=1x1" alt="" width="1" height="1" style="border: none; position: absolute;"></noscript> <div class="printfooter" data-nosnippet="">Obtida de "<a dir="ltr" href="https://pt.wikipedia.org/w/index.php?title=Massa_atómica&oldid=68147518">https://pt.wikipedia.org/w/index.php?title=Massa_atómica&oldid=68147518</a>"</div></div> <div id="catlinks" class="catlinks" data-mw="interface"><div id="mw-normal-catlinks" class="mw-normal-catlinks"><a href="/wiki/Especial:Categorias" title="Especial:Categorias">Categoria</a>: <ul><li><a href="/wiki/Categoria:Estrutura_at%C3%B4mica" title="Categoria:Estrutura atômica">Estrutura atômica</a></li></ul></div><div id="mw-hidden-catlinks" class="mw-hidden-catlinks mw-hidden-cats-hidden">Categorias ocultas: <ul><li><a href="/wiki/Categoria:!Artigos_a_revisar_desde_mar%C3%A7o_de_2011" title="Categoria:!Artigos a revisar desde março de 2011">!Artigos a revisar desde março de 2011</a></li><li><a href="/wiki/Categoria:!Artigos_a_revisar_sem_indica%C3%A7%C3%A3o_de_tema" title="Categoria:!Artigos a revisar sem indicação de tema">!Artigos a revisar sem indicação de tema</a></li><li><a href="/wiki/Categoria:Palavras_que_diferem_em_vers%C3%B5es_da_l%C3%ADngua_portuguesa" title="Categoria:Palavras que diferem em versões da língua portuguesa">Palavras que diferem em versões da língua portuguesa</a></li><li><a href="/wiki/Categoria:!CS1_ingl%C3%AAs-fontes_em_l%C3%ADngua_(en)" title="Categoria:!CS1 inglês-fontes em língua (en)">!CS1 inglês-fontes em língua (en)</a></li></ul></div></div> </div> </main> </div> <div class="mw-footer-container"> <footer id="footer" class="mw-footer" > <ul id="footer-info"> <li id="footer-info-lastmod"> Esta página foi editada pela última vez às 14h02min de 19 de junho de 2024.</li> <li id="footer-info-copyright">Este texto é disponibilizado nos termos da licença <a rel="nofollow" class="external text" href="https://creativecommons.org/licenses/by-sa/4.0/deed.pt">Atribuição-CompartilhaIgual 4.0 Internacional (CC BY-SA 4.0) da Creative Commons</a>; pode estar sujeito a condições adicionais. 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