Massa atom relatif: Perbedaan antara revisi

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k Pierrewee memindahkan halaman Bobot atom ke Massa atom relatif: dari en.wiki:relative atomic mass
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{{distinguish|Massa atom}}
'''BobotMassa atom''' atau '''Berat atomrelatif''' (bahasa Inggris: ''AtomicRelative atomic Weightmas'', simbol: ''A''<sub>r</sub>) adalah suatu [[kuantitas fisik]] tak berdimensi yang merupakan perbandingan [[massa]] rata-rata [[atom]] suatu [[unsur]] terhadap 1/12 massa satu atom [[karbon-12]].<ref name="IUPAC1979">{{cite journal | author = [[International Union of Pure and Applied Chemistry]] | title = Atomic Weights of the Elements 1979 | url = http://www.iupac.org/publications/pac/1980/pdf/5210x2349.pdf | doi = 0033-4545/80/1001-2349$02.00/0 | journal = [[Pure and Applied Chemistry|Pure Appl. Chem.]] | year = 1980 | volume = 52 | pages = 2349–84}}</ref><ref name="GreenBook">{{GreenBookRef2nd|page=41}}</ref> Istilah ini biasanya digunakan juga untuk merujuk pada '''bobot atom relatif''' yang dipublikasikan secara berkala oleh [[International Union of Pure and Applied Chemistry]] (IUPAC)<ref>The latest edition is {{cite journal | author = [[International Union of Pure and Applied Chemistry]] | url = http://www.iupac.org/publications/pac/2006/pdf/7811x2051.pdf | title = Atomic Weights of the Elements 2005 | journal = [[Pure and Applied Chemistry|Pure Appl. Chem.]] | volume = 78 | issue = 11 | pages = 2051–66 | doi = 10.1351/pac200678112051 | year = 2006}}</ref><ref>The updated list of standard atomic weights is expected to be formally published in late 2008. The IUPAC Commission on Isotopic Abundances and Atomic Weights [http://www.iupac.org/objID/Note/nt50112469625981329917907 announced] in August 2007 that the standard atomic weights of the following elements would be revised (new figures quoted here): [[lutetium]] 174.9668(1); [[molybdenum]] 95.96(2); [[nickel]] 58.6934(4); [[ytterbium]] 173.054(5); [[zinc]] 65.38(2). The recommended value for the isotope amount ratio of {{sup|40}}Ar/{{sup|36}}Ar (which could be useful as a [[Scientific control|control measurement]] in [[argon–argon dating]]) was also changed from 296.03(53) to 298.56(31).</ref>. Daftar bobot atom standar dapat ditemukan secara meluas dalam [[buku pelajaran]] kimia, katalog-katalog komersial, dan papan informasi di laboratorium kimia. Penggunaan kata "berat atom" telah mengundang banyak kontroversi, paling tidak sejak tahun 1960-an<ref name="IUPAChist">{{cite journal | first = P. | last = de Bièvre | coauthors = Peiser, H.S. | year = 1992 | title = 'Atomic Weight'—The Name, Its History, Definition, and Units | url = http://www.iupac.org/publications/pac/1992/pdf/6410x1535.pdf | journal = [[Pure and Applied Chemistry|Pure Appl. Chem.]] | volume = 64 | issue = 10 | pages = 1535–43 | doi = 10.1351/pac199264101535}}</ref> (lihat bawah).
 
Bobot atom, berbeda dengan massa atom (massa atom individu), bukanlah [[tetapan fisika]] dan dapat berbeda-beda dari sampel yang satu ke sampel yang lain. Walau demikian, bobot atom cukuplah konstan dalam sampel "normal" untuk digunakan dalam bidang [[kimia]].