The charge on the cobalt ion in the salt CoO is .

The charge of cobalt in the salt is + 2.

Explanation:

The charge of the salt = 0 . This is because it is neutral.

Charge of cobalt = ?

Charge of oxygen = -2 (This is a constant value, it is -2 only in peroxides)

Charge of salt = Charge of cobalt + Charge of oxygen

0 = x + (-2)

x = + 2

The charge of cobalt in the salt is + 2.

i think the answer is terrae but not 100 percent sure. ▓▬▬ §