What are these, or are they the same thing?

Question

Atomic Mass

and

Mass number

Answer 1

they are both the same thing....the measurement of number of protons and neutrons in the nucleus of an atom.

Answer 2

mass number = protons and neutrons

atomic mass=protons

Definitely not the same thing...

Answer 3

atomic mass is the mass of one atom (protons, electrons and neutrons) measured, normally, in atomic mass units. Electrons are so small that they are almost weightles so it is normally simplified to the number or protons and neutrons for more basic chemistry classes.

mass number is the number of protons in one atom. It often tells us how many electrons are present as the positives(protons) and negatives (electrons) must balance out in most cases.