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Related to mass number: Isotopy
The sum of the number of neutrons and protons in an atomic nucleus. Also called nucleon number.
(Atomic Physics) the total number of neutrons and protons in the nucleus of a particular atom. Symbol: A Also called: nucleon number
the number of nucleons in an atomic or isotopic nucleus. Symbol: A
The total number of protons and neutrons in the nucleus of an atom. For example, nitrogen has 7 protons and 7 neutrons in its nucleus, giving it a mass number of 14.
1. The total number of protons and neutrons (nucleons) in the nucleus of an atom.
2. The number of nucleons (protons and neutrons) in the nucleus of an atom.