Question

C. If an electron is added to the outer shell, how will this affect the charge and volume of the atom?

if an electron is added on the outer shell

Answer 1

when an atom gains an electron, it gains a negative charge . it's volume increases as well due to the increase in repulsion between the electrons

Answer 2

An atom that gains or loses an electron becomes an ion. If it gains a negative electron, it becomes a negative ion. If it loses an electron it becomes a positive ion.