相对原子质量表

本相对原子质量表按原子序数排。
 本表数据源自2022年IUPAC元素周期表（IUPAC 2022 standard atomic weights），單同位素質量源自Standard atomic weights of the elements 2021（IUPAC Technical Report） ，以碳十二＝12为标准。
 本表［］内的原子质量为放射元素（除钨、铋、钍、镤、铀，虽然这些元素没有稳定同位素，但有天然放射同位素鎢180、182至184、186，鉍209，釷232，鏷231，鈾235、238，故仍可給予标準原子量）最长半衰期的同位素质量数。

a此元素無穩定同位素，只有放射同位素。四種元素（Bi，Th，Pa，U）有characteristic terrestrial isotopic composition，其標準原子質量is tabulated；其它三十四種元素的標準原子質量cannot determine。

b Ar°(E) values and their uncertainties are given for normal materials and include evaluations of measurement uncertainty as well as natural variations in atomic weight where applicable。The atomic weight of a normal material is expected to lie within the lower and upper endpoints of the standard atomic weight at the current status of knowledge。If the uncertainty in Ar°(E) is considered too large for a user’s purpose for an element with measurable variations in atomic weight，a value of Ar(E) with a lower uncertainty might be obtained by measurement of an individual specimen.

g Geological and biological materials are known in which the element has an isotopic composition outside the limits for normal material。The difference between the atomic weight of the element in such materials and that given in the table may exceed the stated uncertainty.

m Modified isotopic compositions may be found in commercially available material because the material has been subjected to some undisclosed or inadvertent isotopic fractionation。Substantial deviations in atomic weight of the element from that given in the table can occur.

r Range in isotopic composition of normal terrestrial material prevents a more precise standard atomic weight being given；the tabulated value and uncertainty should be applicable to normal material.

参见 
 元素列表
 元素周期表
 同位素列表

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化学元素列表
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化學列表

en:List of elements by atomic weight
ru:Список элементов по атомной массе