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Available in 75 languages" > <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-75" 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">75 languages</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/Massagetal" title="Massagetal – Afrikaans" lang="af" hreflang="af" data-title="Massagetal" data-language-autonym="Afrikaans" data-language-local-name="Afrikaans" class="interlanguage-link-target"><span>Afrikaans</span></a></li><li class="interlanguage-link interwiki-ar mw-list-item"><a href="https://ar.wikipedia.org/wiki/%D8%B9%D8%AF%D8%AF_%D9%83%D8%AA%D9%84%D9%8A" title="عدد كتلي – Arabic" lang="ar" hreflang="ar" data-title="عدد كتلي" data-language-autonym="العربية" data-language-local-name="Arabic" class="interlanguage-link-target"><span>العربية</span></a></li><li class="interlanguage-link interwiki-an mw-list-item"><a href="https://an.wikipedia.org/wiki/Numero_masico" title="Numero masico – Aragonese" lang="an" hreflang="an" data-title="Numero masico" data-language-autonym="Aragonés" data-language-local-name="Aragonese" class="interlanguage-link-target"><span>Aragonés</span></a></li><li class="interlanguage-link interwiki-bn mw-list-item"><a href="https://bn.wikipedia.org/wiki/%E0%A6%86%E0%A6%A3%E0%A6%AC%E0%A6%BF%E0%A6%95_%E0%A6%AD%E0%A6%B0_%E0%A6%B8%E0%A6%82%E0%A6%96%E0%A7%8D%E0%A6%AF%E0%A6%BE" title="আণবিক ভর সংখ্যা – Bangla" lang="bn" hreflang="bn" data-title="আণবিক ভর সংখ্যা" data-language-autonym="বাংলা" data-language-local-name="Bangla" class="interlanguage-link-target"><span>বাংলা</span></a></li><li class="interlanguage-link interwiki-be mw-list-item"><a href="https://be.wikipedia.org/wiki/%D0%9C%D0%B0%D1%81%D0%B0%D0%B2%D1%8B_%D0%BB%D1%96%D0%BA" title="Масавы лік – Belarusian" lang="be" hreflang="be" data-title="Масавы лік" data-language-autonym="Беларуская" data-language-local-name="Belarusian" class="interlanguage-link-target"><span>Беларуская</span></a></li><li class="interlanguage-link interwiki-bg mw-list-item"><a href="https://bg.wikipedia.org/wiki/%D0%9C%D0%B0%D1%81%D0%BE%D0%B2%D0%BE_%D1%87%D0%B8%D1%81%D0%BB%D0%BE" title="Масово число – Bulgarian" lang="bg" hreflang="bg" data-title="Масово число" data-language-autonym="Български" data-language-local-name="Bulgarian" class="interlanguage-link-target"><span>Български</span></a></li><li class="interlanguage-link interwiki-bs mw-list-item"><a href="https://bs.wikipedia.org/wiki/Maseni_broj" title="Maseni broj – Bosnian" lang="bs" hreflang="bs" data-title="Maseni broj" data-language-autonym="Bosanski" data-language-local-name="Bosnian" class="interlanguage-link-target"><span>Bosanski</span></a></li><li class="interlanguage-link interwiki-br mw-list-item"><a href="https://br.wikipedia.org/wiki/Niver_mas" title="Niver mas – Breton" lang="br" hreflang="br" data-title="Niver mas" data-language-autonym="Brezhoneg" data-language-local-name="Breton" class="interlanguage-link-target"><span>Brezhoneg</span></a></li><li class="interlanguage-link interwiki-ca mw-list-item"><a href="https://ca.wikipedia.org/wiki/Nombre_m%C3%A0ssic" title="Nombre màssic – Catalan" lang="ca" hreflang="ca" data-title="Nombre màssic" data-language-autonym="Català" data-language-local-name="Catalan" class="interlanguage-link-target"><span>Català</span></a></li><li class="interlanguage-link interwiki-cs mw-list-item"><a href="https://cs.wikipedia.org/wiki/Nukleonov%C3%A9_%C4%8D%C3%ADslo" title="Nukleonové číslo – Czech" lang="cs" hreflang="cs" data-title="Nukleonové číslo" data-language-autonym="Čeština" data-language-local-name="Czech" class="interlanguage-link-target"><span>Čeština</span></a></li><li class="interlanguage-link interwiki-cy mw-list-item"><a href="https://cy.wikipedia.org/wiki/Rhif_m%C3%A0s" title="Rhif màs – Welsh" lang="cy" hreflang="cy" data-title="Rhif màs" data-language-autonym="Cymraeg" data-language-local-name="Welsh" class="interlanguage-link-target"><span>Cymraeg</span></a></li><li class="interlanguage-link interwiki-de mw-list-item"><a href="https://de.wikipedia.org/wiki/Massenzahl" title="Massenzahl – German" lang="de" hreflang="de" data-title="Massenzahl" data-language-autonym="Deutsch" data-language-local-name="German" class="interlanguage-link-target"><span>Deutsch</span></a></li><li class="interlanguage-link interwiki-et mw-list-item"><a href="https://et.wikipedia.org/wiki/Massiarv" title="Massiarv – Estonian" lang="et" hreflang="et" data-title="Massiarv" data-language-autonym="Eesti" data-language-local-name="Estonian" class="interlanguage-link-target"><span>Eesti</span></a></li><li class="interlanguage-link interwiki-el mw-list-item"><a href="https://el.wikipedia.org/wiki/%CE%9C%CE%B1%CE%B6%CE%B9%CE%BA%CF%8C%CF%82_%CE%B1%CF%81%CE%B9%CE%B8%CE%BC%CF%8C%CF%82" title="Μαζικός αριθμός – Greek" lang="el" hreflang="el" data-title="Μαζικός αριθμός" data-language-autonym="Ελληνικά" data-language-local-name="Greek" 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/Mass_number" title="Mass number – English" lang="en" hreflang="en" data-title="Mass number" data-language-autonym="English" data-language-local-name="English" class="interlanguage-link-target"><span>English</span></a></li><li class="interlanguage-link interwiki-es mw-list-item"><a href="https://es.wikipedia.org/wiki/N%C3%BAmero_m%C3%A1sico" title="Número másico – Spanish" lang="es" hreflang="es" data-title="Número másico" data-language-autonym="Español" data-language-local-name="Spanish" class="interlanguage-link-target"><span>Español</span></a></li><li class="interlanguage-link interwiki-eo mw-list-item"><a href="https://eo.wikipedia.org/wiki/Masnombro" title="Masnombro – Esperanto" lang="eo" hreflang="eo" data-title="Masnombro" data-language-autonym="Esperanto" data-language-local-name="Esperanto" class="interlanguage-link-target"><span>Esperanto</span></a></li><li class="interlanguage-link interwiki-eu mw-list-item"><a href="https://eu.wikipedia.org/wiki/Masa-zenbaki" title="Masa-zenbaki – Basque" lang="eu" hreflang="eu" data-title="Masa-zenbaki" data-language-autonym="Euskara" data-language-local-name="Basque" 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%B9%D8%AF%D8%AF_%D8%AC%D8%B1%D9%85%DB%8C" title="عدد جرمی – Persian" lang="fa" hreflang="fa" data-title="عدد جرمی" data-language-autonym="فارسی" data-language-local-name="Persian" class="interlanguage-link-target"><span>فارسی</span></a></li><li class="interlanguage-link interwiki-hif mw-list-item"><a href="https://hif.wikipedia.org/wiki/Mass_number" title="Mass number – Fiji Hindi" lang="hif" hreflang="hif" data-title="Mass number" 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-fr mw-list-item"><a href="https://fr.wikipedia.org/wiki/Nombre_de_masse" title="Nombre de masse – French" lang="fr" hreflang="fr" data-title="Nombre de masse" data-language-autonym="Français" data-language-local-name="French" 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/Numar_di_masse" title="Numar di masse – Friulian" lang="fur" hreflang="fur" data-title="Numar di masse" data-language-autonym="Furlan" data-language-local-name="Friulian" class="interlanguage-link-target"><span>Furlan</span></a></li><li class="interlanguage-link interwiki-ga mw-list-item"><a href="https://ga.wikipedia.org/wiki/Maisuimhir" title="Maisuimhir – Irish" lang="ga" hreflang="ga" data-title="Maisuimhir" data-language-autonym="Gaeilge" data-language-local-name="Irish" 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/N%C3%BAmero_m%C3%A1sico" title="Número másico – Galician" lang="gl" hreflang="gl" data-title="Número másico" data-language-autonym="Galego" data-language-local-name="Galician" class="interlanguage-link-target"><span>Galego</span></a></li><li class="interlanguage-link interwiki-ko mw-list-item"><a href="https://ko.wikipedia.org/wiki/%EC%A7%88%EB%9F%89%EC%88%98" title="질량수 – Korean" lang="ko" hreflang="ko" data-title="질량수" data-language-autonym="한국어" data-language-local-name="Korean" class="interlanguage-link-target"><span>한국어</span></a></li><li class="interlanguage-link interwiki-hy mw-list-item"><a href="https://hy.wikipedia.org/wiki/%D4%B6%D5%A1%D5%B6%D5%A3%D5%BE%D5%A1%D5%AE%D5%A1%D5%B5%D5%AB%D5%B6_%D5%A9%D5%AB%D5%BE" title="Զանգվածային թիվ – Armenian" lang="hy" hreflang="hy" data-title="Զանգվածային թիվ" data-language-autonym="Հայերեն" data-language-local-name="Armenian" class="interlanguage-link-target"><span>Հայերեն</span></a></li><li class="interlanguage-link interwiki-hi mw-list-item"><a href="https://hi.wikipedia.org/wiki/%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_%E0%A4%B8%E0%A4%82%E0%A4%96%E0%A5%8D%E0%A4%AF%E0%A4%BE" title="द्रव्यमान संख्या – Hindi" lang="hi" hreflang="hi" data-title="द्रव्यमान संख्या" data-language-autonym="हिन्दी" data-language-local-name="Hindi" class="interlanguage-link-target"><span>हिन्दी</span></a></li><li class="interlanguage-link interwiki-hr mw-list-item"><a href="https://hr.wikipedia.org/wiki/Maseni_broj" title="Maseni broj – Croatian" lang="hr" hreflang="hr" data-title="Maseni broj" data-language-autonym="Hrvatski" data-language-local-name="Croatian" class="interlanguage-link-target"><span>Hrvatski</span></a></li><li class="interlanguage-link interwiki-id mw-list-item"><a href="https://id.wikipedia.org/wiki/Nomor_massa" title="Nomor massa – Indonesian" lang="id" hreflang="id" data-title="Nomor massa" data-language-autonym="Bahasa Indonesia" data-language-local-name="Indonesian" class="interlanguage-link-target"><span>Bahasa Indonesia</span></a></li><li class="interlanguage-link interwiki-ia mw-list-item"><a href="https://ia.wikipedia.org/wiki/Numero_de_massa" title="Numero de massa – Interlingua" lang="ia" hreflang="ia" data-title="Numero de massa" data-language-autonym="Interlingua" data-language-local-name="Interlingua" class="interlanguage-link-target"><span>Interlingua</span></a></li><li class="interlanguage-link interwiki-is mw-list-item"><a href="https://is.wikipedia.org/wiki/Massatala" title="Massatala – Icelandic" lang="is" hreflang="is" data-title="Massatala" data-language-autonym="Íslenska" data-language-local-name="Icelandic" 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/Numero_di_massa" title="Numero di massa – Italian" lang="it" hreflang="it" data-title="Numero di massa" data-language-autonym="Italiano" data-language-local-name="Italian" class="interlanguage-link-target"><span>Italiano</span></a></li><li class="interlanguage-link interwiki-he mw-list-item"><a href="https://he.wikipedia.org/wiki/%D7%9E%D7%A1%D7%A4%D7%A8_%D7%9E%D7%A1%D7%94" title="מספר מסה – Hebrew" lang="he" hreflang="he" data-title="מספר מסה" data-language-autonym="עברית" data-language-local-name="Hebrew" class="interlanguage-link-target"><span>עברית</span></a></li><li class="interlanguage-link interwiki-kn mw-list-item"><a href="https://kn.wikipedia.org/wiki/%E0%B2%B0%E0%B2%BE%E0%B2%B6%E0%B2%BF%E0%B2%B8%E0%B2%82%E0%B2%96%E0%B3%8D%E0%B2%AF%E0%B3%86" title="ರಾಶಿಸಂಖ್ಯೆ – Kannada" lang="kn" hreflang="kn" data-title="ರಾಶಿಸಂಖ್ಯೆ" data-language-autonym="ಕನ್ನಡ" data-language-local-name="Kannada" class="interlanguage-link-target"><span>ಕನ್ನಡ</span></a></li><li class="interlanguage-link interwiki-ka mw-list-item"><a href="https://ka.wikipedia.org/wiki/%E1%83%9B%E1%83%90%E1%83%A1%E1%83%A3%E1%83%A0%E1%83%98_%E1%83%A0%E1%83%98%E1%83%AA%E1%83%AE%E1%83%95%E1%83%98" title="მასური რიცხვი – Georgian" lang="ka" hreflang="ka" data-title="მასური რიცხვი" data-language-autonym="ქართული" data-language-local-name="Georgian" class="interlanguage-link-target"><span>ქართული</span></a></li><li class="interlanguage-link interwiki-kk mw-list-item"><a href="https://kk.wikipedia.org/wiki/%D0%9C%D0%B0%D1%81%D1%81%D0%B0%D0%BB%D1%8B%D2%9B_%D1%81%D0%B0%D0%BD" title="Массалық сан – Kazakh" lang="kk" hreflang="kk" data-title="Массалық сан" data-language-autonym="Қазақша" data-language-local-name="Kazakh" class="interlanguage-link-target"><span>Қазақша</span></a></li><li class="interlanguage-link interwiki-ht mw-list-item"><a href="https://ht.wikipedia.org/wiki/Nonm_mas" title="Nonm mas – Haitian Creole" lang="ht" hreflang="ht" data-title="Nonm mas" data-language-autonym="Kreyòl ayisyen" data-language-local-name="Haitian Creole" class="interlanguage-link-target"><span>Kreyòl ayisyen</span></a></li><li class="interlanguage-link interwiki-ku mw-list-item"><a href="https://ku.wikipedia.org/wiki/Hejmara_baristey%C3%AE" title="Hejmara baristeyî – Kurdish" lang="ku" hreflang="ku" data-title="Hejmara baristeyî" data-language-autonym="Kurdî" data-language-local-name="Kurdish" class="interlanguage-link-target"><span>Kurdî</span></a></li><li class="interlanguage-link interwiki-lv mw-list-item"><a href="https://lv.wikipedia.org/wiki/Masas_skaitlis" title="Masas skaitlis – Latvian" lang="lv" hreflang="lv" data-title="Masas skaitlis" data-language-autonym="Latviešu" data-language-local-name="Latvian" class="interlanguage-link-target"><span>Latviešu</span></a></li><li class="interlanguage-link interwiki-lmo mw-list-item"><a href="https://lmo.wikipedia.org/wiki/N%C3%BCmer_de_massa" title="Nümer de massa – Lombard" lang="lmo" hreflang="lmo" data-title="Nümer de massa" data-language-autonym="Lombard" data-language-local-name="Lombard" class="interlanguage-link-target"><span>Lombard</span></a></li><li class="interlanguage-link interwiki-hu mw-list-item"><a href="https://hu.wikipedia.org/wiki/T%C3%B6megsz%C3%A1m" title="Tömegszám – Hungarian" lang="hu" hreflang="hu" data-title="Tömegszám" data-language-autonym="Magyar" data-language-local-name="Hungarian" class="interlanguage-link-target"><span>Magyar</span></a></li><li class="interlanguage-link interwiki-ml mw-list-item"><a href="https://ml.wikipedia.org/wiki/%E0%B4%AA%E0%B4%BF%E0%B4%A3%E0%B5%8D%E0%B4%A1%E0%B4%B8%E0%B4%82%E0%B4%96%E0%B5%8D%E0%B4%AF" title="പിണ്ഡസംഖ്യ – Malayalam" lang="ml" hreflang="ml" data-title="പിണ്ഡസംഖ്യ" data-language-autonym="മലയാളം" data-language-local-name="Malayalam" class="interlanguage-link-target"><span>മലയാളം</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%B5%E0%A4%B8%E0%A5%8D%E0%A4%A4%E0%A5%81%E0%A4%AE%E0%A4%BE%E0%A4%A8%E0%A4%BE%E0%A4%82%E0%A4%95" title="अणुवस्तुमानांक – Marathi" lang="mr" hreflang="mr" data-title="अणुवस्तुमानांक" data-language-autonym="मराठी" data-language-local-name="Marathi" 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/Nombor_jisim" title="Nombor jisim – Malay" lang="ms" hreflang="ms" data-title="Nombor jisim" data-language-autonym="Bahasa Melayu" data-language-local-name="Malay" class="interlanguage-link-target"><span>Bahasa Melayu</span></a></li><li class="interlanguage-link interwiki-mn mw-list-item"><a href="https://mn.wikipedia.org/wiki/%D0%96%D0%B8%D0%BD%D0%B3%D0%B8%D0%B9%D0%BD_%D1%82%D0%BE%D0%BE" title="Жингийн тоо – Mongolian" lang="mn" hreflang="mn" data-title="Жингийн тоо" data-language-autonym="Монгол" data-language-local-name="Mongolian" class="interlanguage-link-target"><span>Монгол</span></a></li><li class="interlanguage-link interwiki-nl mw-list-item"><a href="https://nl.wikipedia.org/wiki/Massagetal" title="Massagetal – Dutch" lang="nl" hreflang="nl" data-title="Massagetal" data-language-autonym="Nederlands" data-language-local-name="Dutch" class="interlanguage-link-target"><span>Nederlands</span></a></li><li class="interlanguage-link interwiki-ja mw-list-item"><a href="https://ja.wikipedia.org/wiki/%E8%B3%AA%E9%87%8F%E6%95%B0" title="質量数 – Japanese" lang="ja" hreflang="ja" data-title="質量数" data-language-autonym="日本語" data-language-local-name="Japanese" class="interlanguage-link-target"><span>日本語</span></a></li><li class="interlanguage-link interwiki-ce mw-list-item"><a href="https://ce.wikipedia.org/wiki/%D0%9C%D0%B0%D1%81%D1%81%D0%B0%D0%BD_%D1%82%D0%B5%D1%80%D0%B0%D1%85%D1%8C" title="Массан терахь – Chechen" lang="ce" hreflang="ce" data-title="Массан терахь" data-language-autonym="Нохчийн" data-language-local-name="Chechen" class="interlanguage-link-target"><span>Нохчийн</span></a></li><li class="interlanguage-link interwiki-no mw-list-item"><a href="https://no.wikipedia.org/wiki/Massetall" title="Massetall – Norwegian Bokmål" lang="nb" hreflang="nb" data-title="Massetall" data-language-autonym="Norsk bokmål" data-language-local-name="Norwegian Bokmål" class="interlanguage-link-target"><span>Norsk bokmål</span></a></li><li class="interlanguage-link interwiki-oc mw-list-item"><a href="https://oc.wikipedia.org/wiki/Nombre_de_massa" title="Nombre de massa – Occitan" lang="oc" hreflang="oc" data-title="Nombre de massa" data-language-autonym="Occitan" data-language-local-name="Occitan" class="interlanguage-link-target"><span>Occitan</span></a></li><li class="interlanguage-link interwiki-nds mw-list-item"><a href="https://nds.wikipedia.org/wiki/Massentall" title="Massentall – Low German" lang="nds" hreflang="nds" data-title="Massentall" data-language-autonym="Plattdüütsch" data-language-local-name="Low German" class="interlanguage-link-target"><span>Plattdüütsch</span></a></li><li class="interlanguage-link interwiki-pl mw-list-item"><a href="https://pl.wikipedia.org/wiki/Liczba_masowa" title="Liczba masowa – Polish" lang="pl" hreflang="pl" data-title="Liczba masowa" data-language-autonym="Polski" data-language-local-name="Polish" class="interlanguage-link-target"><span>Polski</span></a></li><li class="interlanguage-link interwiki-pt mw-list-item"><a href="https://pt.wikipedia.org/wiki/N%C3%BAmero_de_massa" title="Número de massa – Portuguese" lang="pt" hreflang="pt" data-title="Número de massa" data-language-autonym="Português" data-language-local-name="Portuguese" class="interlanguage-link-target"><span>Português</span></a></li><li class="interlanguage-link interwiki-ro mw-list-item"><a href="https://ro.wikipedia.org/wiki/Num%C4%83r_de_mas%C4%83" title="Număr de masă – Romanian" lang="ro" hreflang="ro" data-title="Număr de masă" data-language-autonym="Română" data-language-local-name="Romanian" 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%9C%D0%B0%D1%81%D1%81%D0%BE%D0%B2%D0%BE%D0%B5_%D1%87%D0%B8%D1%81%D0%BB%D0%BE" title="Массовое число – Russian" lang="ru" hreflang="ru" data-title="Массовое число" data-language-autonym="Русский" data-language-local-name="Russian" class="interlanguage-link-target"><span>Русский</span></a></li><li class="interlanguage-link interwiki-sq mw-list-item"><a href="https://sq.wikipedia.org/wiki/Numri_i_mas%C3%ABs" title="Numri i masës – Albanian" lang="sq" hreflang="sq" data-title="Numri i masës" data-language-autonym="Shqip" data-language-local-name="Albanian" class="interlanguage-link-target"><span>Shqip</span></a></li><li class="interlanguage-link interwiki-si mw-list-item"><a href="https://si.wikipedia.org/wiki/%E0%B7%83%E0%B7%8A%E0%B6%9A%E0%B6%B1%E0%B7%8A%E0%B6%B0_%E0%B6%9A%E0%B7%8A%E2%80%8D%E0%B6%BB%E0%B6%B8%E0%B7%8F%E0%B6%82%E0%B6%9A%E0%B6%BA" title="ස්කන්ධ ක්‍රමාංකය – Sinhala" lang="si" hreflang="si" data-title="ස්කන්ධ ක්‍රමාංකය" data-language-autonym="සිංහල" data-language-local-name="Sinhala" class="interlanguage-link-target"><span>සිංහල</span></a></li><li class="interlanguage-link interwiki-sk mw-list-item"><a href="https://sk.wikipedia.org/wiki/Nukle%C3%B3nov%C3%A9_%C4%8D%C3%ADslo" title="Nukleónové číslo – Slovak" lang="sk" hreflang="sk" data-title="Nukleónové číslo" data-language-autonym="Slovenčina" data-language-local-name="Slovak" 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/Masno_%C5%A1tevilo" title="Masno število – Slovenian" lang="sl" hreflang="sl" data-title="Masno število" data-language-autonym="Slovenščina" data-language-local-name="Slovenian" class="interlanguage-link-target"><span>Slovenščina</span></a></li><li class="interlanguage-link interwiki-sr mw-list-item"><a href="https://sr.wikipedia.org/wiki/%D0%9C%D0%B0%D1%81%D0%B5%D0%BD%D0%B8_%D0%B1%D1%80%D0%BE%D1%98" title="Масени број – Serbian" lang="sr" hreflang="sr" data-title="Масени број" data-language-autonym="Српски / srpski" data-language-local-name="Serbian" class="interlanguage-link-target"><span>Српски / srpski</span></a></li><li class="interlanguage-link interwiki-sh mw-list-item"><a href="https://sh.wikipedia.org/wiki/Maseni_broj" title="Maseni broj – Serbo-Croatian" lang="sh" hreflang="sh" data-title="Maseni broj" data-language-autonym="Srpskohrvatski / српскохрватски" data-language-local-name="Serbo-Croatian" class="interlanguage-link-target"><span>Srpskohrvatski / српскохрватски</span></a></li><li class="interlanguage-link interwiki-fi mw-list-item"><a href="https://fi.wikipedia.org/wiki/Massaluku" title="Massaluku – Finnish" lang="fi" hreflang="fi" data-title="Massaluku" data-language-autonym="Suomi" data-language-local-name="Finnish" class="interlanguage-link-target"><span>Suomi</span></a></li><li class="interlanguage-link interwiki-sv mw-list-item"><a href="https://sv.wikipedia.org/wiki/Masstal" title="Masstal – Swedish" lang="sv" hreflang="sv" data-title="Masstal" data-language-autonym="Svenska" data-language-local-name="Swedish" class="interlanguage-link-target"><span>Svenska</span></a></li><li class="interlanguage-link interwiki-tl mw-list-item"><a href="https://tl.wikipedia.org/wiki/Bilang_na_pangmasa" title="Bilang na pangmasa – Tagalog" lang="tl" hreflang="tl" data-title="Bilang na pangmasa" data-language-autonym="Tagalog" data-language-local-name="Tagalog" class="interlanguage-link-target"><span>Tagalog</span></a></li><li class="interlanguage-link interwiki-ta mw-list-item"><a href="https://ta.wikipedia.org/wiki/%E0%AE%A4%E0%AE%BF%E0%AE%A3%E0%AE%BF%E0%AE%B5%E0%AF%86%E0%AE%A3%E0%AF%8D" title="திணிவெண் – Tamil" lang="ta" hreflang="ta" data-title="திணிவெண்" data-language-autonym="தமிழ்" data-language-local-name="Tamil" class="interlanguage-link-target"><span>தமிழ்</span></a></li><li class="interlanguage-link interwiki-th mw-list-item"><a href="https://th.wikipedia.org/wiki/%E0%B9%80%E0%B8%A5%E0%B8%82%E0%B8%A1%E0%B8%A7%E0%B8%A5" title="เลขมวล – Thai" lang="th" hreflang="th" data-title="เลขมวล" data-language-autonym="ไทย" data-language-local-name="Thai" class="interlanguage-link-target"><span>ไทย</span></a></li><li class="interlanguage-link interwiki-tg mw-list-item"><a href="https://tg.wikipedia.org/wiki/%D0%90%D0%B4%D0%B0%D0%B4%D0%B8_%D0%BC%D0%B0%D1%81%D1%81%D0%B0%D0%B2%D3%A3" title="Адади массавӣ – Tajik" lang="tg" hreflang="tg" data-title="Адади массавӣ" data-language-autonym="Тоҷикӣ" data-language-local-name="Tajik" class="interlanguage-link-target"><span>Тоҷикӣ</span></a></li><li class="interlanguage-link interwiki-tr mw-list-item"><a href="https://tr.wikipedia.org/wiki/K%C3%BCtle_numaras%C4%B1" title="Kütle numarası – Turkish" lang="tr" hreflang="tr" data-title="Kütle numarası" data-language-autonym="Türkçe" data-language-local-name="Turkish" 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%9C%D0%B0%D1%81%D0%BE%D0%B2%D0%B5_%D1%87%D0%B8%D1%81%D0%BB%D0%BE" title="Масове число – Ukrainian" lang="uk" hreflang="uk" data-title="Масове число" data-language-autonym="Українська" data-language-local-name="Ukrainian" class="interlanguage-link-target"><span>Українська</span></a></li><li class="interlanguage-link interwiki-vec mw-list-item"><a href="https://vec.wikipedia.org/wiki/N%C3%B9maro_de_masa" title="Nùmaro de masa – Venetian" lang="vec" hreflang="vec" data-title="Nùmaro de masa" data-language-autonym="Vèneto" data-language-local-name="Venetian" class="interlanguage-link-target"><span>Vèneto</span></a></li><li class="interlanguage-link interwiki-vi mw-list-item"><a href="https://vi.wikipedia.org/wiki/S%E1%BB%91_kh%E1%BB%91i" title="Số khối – Vietnamese" lang="vi" hreflang="vi" data-title="Số khối" data-language-autonym="Tiếng Việt" data-language-local-name="Vietnamese" class="interlanguage-link-target"><span>Tiếng Việt</span></a></li><li class="interlanguage-link interwiki-vls mw-list-item"><a href="https://vls.wikipedia.org/wiki/Massagetal" title="Massagetal – West Flemish" lang="vls" hreflang="vls" data-title="Massagetal" data-language-autonym="West-Vlams" data-language-local-name="West Flemish" class="interlanguage-link-target"><span>West-Vlams</span></a></li><li class="interlanguage-link interwiki-wuu mw-list-item"><a href="https://wuu.wikipedia.org/wiki/%E8%B4%A8%E9%87%8F%E6%95%B0" title="质量数 – Wu" lang="wuu" hreflang="wuu" data-title="质量数" 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-zh-yue mw-list-item"><a href="https://zh-yue.wikipedia.org/wiki/%E8%B3%AA%E9%87%8F%E6%95%B8" title="質量數 – Cantonese" lang="yue" hreflang="yue" data-title="質量數" data-language-autonym="粵語" data-language-local-name="Cantonese" class="interlanguage-link-target"><span>粵語</span></a></li><li class="interlanguage-link interwiki-zh mw-list-item"><a href="https://zh.wikipedia.org/wiki/%E8%B3%AA%E9%87%8F%E6%95%B8" title="質量數 – Chinese" lang="zh" hreflang="zh" data-title="質量數" data-language-autonym="中文" data-language-local-name="Chinese" 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class="reference"><a href="#cite_note-moore-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 20">: 20 </span></sup> The mass number is different for each <a href="/wiki/Isotope" title="Isotope">isotope</a> of a <a href="/wiki/Chemical_element" title="Chemical element">chemical element</a>. </p><p>We write a mass number after an element's name or as a superscript to the left of an element's symbol. For example, the most common isotope of <a href="/wiki/Carbon" title="Carbon">carbon</a> has 6 protons and 6 neutrons. We write it as carbon-12 or <sup>12</sup>C. </p><p>Mass number is not the same as: </p> <ul><li><b><a href="/wiki/Atomic_number" title="Atomic number">atomic number</a></b> (symbol: <b>Z</b>), which is the number of protons in a nucleus of an atom</li> <li><b><a href="/wiki/Atomic_mass" title="Atomic mass">atomic mass</a></b> (symbol: <i>m</i><sub>a</sub>), which is the mass of a single atom, commonly expressed in <a href="/wiki/Atomic_mass_unit" class="mw-redirect" title="Atomic mass unit">unified atomic mass units</a></li> <li><b><a href="/wiki/Relative_atomic_mass" title="Relative atomic mass">relative atomic mass</a></b> (symbol: <i>A</i><sub>r</sub>, also called <i>atomic weight</i>), which is the ratio of the average mass per atom of an element from a given sample to 1/12 the mass of a carbon-12 atom.</li></ul> <p>The difference between the mass number and the atomic number gives the number of neutrons (<i>N</i>) in a given nucleus: <i>N </i>= <i>A </i>− <i>Z</i>.<sup id="cite_ref-moore_1-1" class="reference"><a href="#cite_note-moore-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 44">: 44 </span></sup> </p><p>The mass number is not shown on the <a href="/wiki/Periodic_table" title="Periodic table">periodic table</a>.<sup id="cite_ref-moore_1-2" class="reference"><a href="#cite_note-moore-1"><span class="cite-bracket">[</span>1<span class="cite-bracket">]</span></a></sup><sup class="reference nowrap"><span title="Page / location: 21">: 21 </span></sup> For each element, what is shown is the <i>standard atomic weight</i> and the <i>atomic number</i>. </p> <div class="mw-heading mw-heading2"><h2 id="References">References</h2><span class="mw-editsection"><span class="mw-editsection-bracket">[</span><a href="/w/index.php?title=Mass_number&veaction=edit&section=1" title="Change section: References" class="mw-editsection-visualeditor"><span>change</span></a><span class="mw-editsection-divider"> | </span><a href="/w/index.php?title=Mass_number&action=edit&section=1" title="Edit section's source code: References"><span>change source</span></a><span class="mw-editsection-bracket">]</span></span></div> <ol class="references"> <li id="cite_note-moore-1"><span class="mw-cite-backlink">↑ <sup><a href="#cite_ref-moore_1-0">1.0</a></sup> <sup><a href="#cite_ref-moore_1-1">1.1</a></sup> <sup><a href="#cite_ref-moore_1-2">1.2</a></sup></span> <span class="reference-text"><style data-mw-deduplicate="TemplateStyles:r9724332">.mw-parser-output cite.citation{font-style:inherit;word-wrap:break-word}.mw-parser-output .citation q{quotes:"\"""\"""'""'"}.mw-parser-output .citation:target{background-color:rgba(0,127,255,0.133)}.mw-parser-output .id-lock-free.id-lock-free a{background:url("//upload.wikimedia.org/wikipedia/commons/6/65/Lock-green.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-limited.id-lock-limited a,.mw-parser-output .id-lock-registration.id-lock-registration a{background:url("//upload.wikimedia.org/wikipedia/commons/d/d6/Lock-gray-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .id-lock-subscription.id-lock-subscription a{background:url("//upload.wikimedia.org/wikipedia/commons/a/aa/Lock-red-alt-2.svg")right 0.1em center/9px no-repeat}.mw-parser-output .cs1-ws-icon a{background:url("//upload.wikimedia.org/wikipedia/commons/4/4c/Wikisource-logo.svg")right 0.1em center/12px no-repeat}body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-free a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-limited a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-registration a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .id-lock-subscription a,body:not(.skin-timeless):not(.skin-minerva) .mw-parser-output .cs1-ws-icon a{background-size:contain;padding:0 1em 0 0}.mw-parser-output .cs1-code{color:inherit;background:inherit;border:none;padding:inherit}.mw-parser-output .cs1-hidden-error{display:none;color:var(--color-error,#d33)}.mw-parser-output .cs1-visible-error{color:var(--color-error,#d33)}.mw-parser-output .cs1-maint{display:none;color:#085;margin-left:0.3em}.mw-parser-output .cs1-kern-left{padding-left:0.2em}.mw-parser-output .cs1-kern-right{padding-right:0.2em}.mw-parser-output .citation .mw-selflink{font-weight:inherit}@media screen{.mw-parser-output .cs1-format{font-size:95%}html.skin-theme-clientpref-night .mw-parser-output .cs1-maint{color:#18911f}}@media screen and (prefers-color-scheme:dark){html.skin-theme-clientpref-os .mw-parser-output .cs1-maint{color:#18911f}}</style><cite id="CITEREFMoore2010" class="citation book cs1">Moore, John T. (2010). <a rel="nofollow" class="external text" href="https://archive.org/details/chemistryessenti0000moor"><i>Chemistry Essentials For Dummies</i></a>. Wiley. <a href="/wiki/ISBN_(identifier)" class="mw-redirect" title="ISBN (identifier)">ISBN</a> <a href="/wiki/Special:BookSources/978-0-470-61836-3" title="Special:BookSources/978-0-470-61836-3"><bdi>978-0-470-61836-3</bdi></a>.</cite><span title="ctx_ver=Z39.88-2004&rft_val_fmt=info%3Aofi%2Ffmt%3Akev%3Amtx%3Abook&rft.genre=book&rft.btitle=Chemistry+Essentials+For+Dummies&rft.pub=Wiley&rft.date=2010&rft.isbn=978-0-470-61836-3&rft.aulast=Moore&rft.aufirst=John+T.&rft_id=https%3A%2F%2Farchive.org%2Fdetails%2Fchemistryessenti0000moor&rfr_id=info%3Asid%2Fsimple.wikipedia.org%3AMass+number" class="Z3988"></span></span> </li> </ol> <p><br /> </p> <div class="boilerplate metadata plainlinks" id="stub"><span typeof="mw:File"><a href="/wiki/File:Chem_template.svg" class="mw-file-description"><img alt="" src="//upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Chem_template.svg/30px-Chem_template.svg.png" decoding="async" width="30" height="30" class="mw-file-element" srcset="//upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Chem_template.svg/45px-Chem_template.svg.png 1.5x, //upload.wikimedia.org/wikipedia/commons/thumb/a/ac/Chem_template.svg/60px-Chem_template.svg.png 2x" data-file-width="400" data-file-height="400" /></a></span> <i>This <a href="/wiki/Wikipedia:Stub" title="Wikipedia:Stub">short article</a> about <a href="/wiki/Category:Chemistry_stubs" title="Category:Chemistry stubs">chemistry</a> can be made longer. 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