posted by Alex .
When two identical ions are separated by a distance of 5.9 multiplied by 10-10 m, the electrostatic force each exerts on the other is 6.0 multiplied by 10-9 N. How many electrons are missing from each ion?
Solve for the charge of each ion using the Coulomb equation. That should give you an integral number of the electron charge, e.
That multiple will be the answer to your question.