Question

Using the periodic table and your knowledge of atomic structure. Cobalt (Co) and nickel (Ni) have almost identical atomic mass numbers. Comparing the typical nickel and cobalt atoms, which statement best describes the atoms?
A) Nickel has one more neutron.
B) Cobalt has one less proton.
C) Both atoms will have the same number of protons.
D) Both atoms will have the same number of neutrons.

Answer 1

Ni
28 protons = atomic number

Co
27 protons = atomic number

Answer 2

Cobalt has one less proton