Chemical nomenclature of ions I'm a very beginner in chemistry. The book I'm studying says that an ion is an atom, or a collection of atoms, that has an electric charge, then it writes about the difference between molecules and ions. What I'm wondering is, if I consider a unit of, say, sodium chloride (by unit I mean one atom of sodium plus one atom of chlorine), should I say "a molecule of s. chloride" or "an ion of s. chloride"?
It is said: one formula unit of sodium chloride.