relative atomic mass

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relative atomic mass

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relative atomic mass

1. (physics) The ratio of the average mass per atom of the naturally occurring form of an element to 1/12 of the mass of a carbon-12 atom. Symbol A_r; abbreviation RAM or r.a.m. For elements with several isotopes, the most stable isotope is treated as the representative.

• atomic weight (deprecated synonym)

• atomic mass
• atomic number
• standard atomic weight