Question

define atomic mass ?​

Answer 1

Answer:

the mass of an atom of a chemical element expressed in atomic mass units. It is approximately equivalent to the number of protons and neutrons in the atom (the mass number) or to the average number allowing for the relative abundances of different isotopes.

Answer 2

Answer:

The atomic mass of a single atom is simply its total mass and is typically expressed in atomic mass units or amu. By definition, an atom of carbon with six neutrons, carbon-12, has an atomic mass of 12 amu

Explanation:

The answer to 'what is atomic mass' is this: the total mass of the protons, neutrons, and electrons in a single atom when it is at rest. ... Chemists used a scale that showed that the natural mixture of oxygen isotopes had an atomic mass 16. Physicists assigned 16 to the atomic mass of the most common oxygen isotope.