Question

An atom has a mass number of 30 and 16 neutrons. what is the atomic number of this atom? express your answer as an integer.

Answer 1

Atomic numbers of atoms are simply the number of protons present in the nucleus. Mass numbers of atoms consist of the sum of the protons and neutrons, so
if the mass number is 30, and there are 16 neutrons present:
Mass=Protons+Neutrons
30=Protons+16
30-16=Protons
14 Protons
Atomic Number=14