Mass-number Synonyms

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. Isotopes of elements are distinguished by their mass number; for example, carbon-12 and carbon-14 have mass numbers of 12 and 14 respectively.
  1. atomic-mass
  2. atomic-weight
  3. atomic-number
  4. atomic volume
  5. nucleon-number
The sum of the number of neutrons and protons in an atomic nucleus
  1. nucleon-number