The magnitude of the electrostatic force between two identical ions that are separated by a distance of 5.0 x10^−10 m is 9.20 x 10^−10 n.
(a) what is the charge (in coulombs) of each ion?

To solve this problem, we apply the concepts related to the electrostatic force proposed by Coulomb's law. This force can be expressed as

Here

k = Coulomb's constant

= Charge of each object

d = Distance between objects

We have that the charge are the same, and the distance and the force are

Replacing we have,

Solving for q,

Therefore the charge of each ion is