Question

define. atomic mass number​

Answer 1

The mass number (symbol A, from the German word Atomgewicht [atomic weight]), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. ... The mass number is different for each different isotope of a chemical element.

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Answer 2

Answer:

The atomic number uniquely identifies a chemical element. It is identical to the charge number of the nucleus. In an uncharged atom, the atomic number is also equal to the number of electrons. The sum of the atomic number Z and the number of neutrons N gives the mass number A of an atom.

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