Question

Gallium is an element with an atomic number of 31 and an atomic mass of 70 amu (rounded). With this information, identify the number of protons, neutrons, and electrons possessed by a gallium atom.

Answer 1

1.) The number of protons is the atomic number. The number of electrons is the same as the number of protons.
31 protons
31 electrons

2.) The number of neutrons is the atomic mass - atomic number. 70 - 31 = 39.
39 neutrons

3.) 31 protons
31 electrons
39 neutrons