Question

What is the charge of a hypothetical ion with 85 protons and 87 electrons?

Answer 1

There is a charge of -2 on an ion.
A neutral atom always have equal number of protons and electrons. if an atom loses and electron, an ion gets positive charge and if an atom gains electron it gets negative charge.
An atom with 85 protons means it also have 85 electrons but when it gains two electrons it becomes ion and then the number of electrons is 87. So that is why an ion have -2 charge.