Question

What could be done to change this carbide ion to a neutral carbon atom? remove 2 electrons add 2 electrons remove 4 electrons add 4 electrons

Answer 1

A carbide ion is an anion of carbon atom with two carbon atoms with a triple bond connected to each other. Since this carbide ion is a negatively charged ion, in order to convert carbide ion to its neutral carbon atom, it has to give up/remove four electrons.