Atomic Mass: The atomic mass of an atom is the sum of the protons and neutrons in its nucleus. It is expressed in atomic mass units (amu). For example, Carbon-12, ...

amu - atomic mass unit, a historic unit for atomic weight - it is based on the 1/16th part of the 16 O mass. Used in discussions, should not be used in publications. Basepeak – this is the most ...

DISCUSSING the unit of atomic weight before Section A (Physics) at the meeting of the British Association in London on Sept. 28, Dr. F. W. Aston contrasted the point of view of the physicist and ...