
Andrew M. answered 01/24/16
Tutor
New to Wyzant
Mathematics - Algebra a Specialty / F.I.T. Grad - B.S. w/Honors
Atomic mass is the weighted average of the mass of
naturally occurring isotopes of an element. Since the
mass of electrons is negligible in comparisom, atomic
mass is virtually the same as the mass number which is
found by adding the protons and neutrons in the
nucleus of an element.