Question

How is net charge found?

Answer 1

Hopefully correctly.

Explanation:

See this old answer. And here for a specific example.

Given a specific atom, you know precisely just how many protons, how many fundamental, positively charged particles, are contained in the atom's nucleus. How do you know this? The net charge of an atom is the excess or deficiency of electrons. Note that this exercise is a formalism; assignment of charge, however, certainly makes the writing of redox reactions and processes easier.