Formulas for ionic compounds. Chemical names. The International Union of Pure and Applied Chemistry (IUPAC) names compounds Chemical names always have two parts: one for each type of ion in it. Salt (Sodium Chloride) is made from a positive sodium ion and a negative chlorine ion.
Ex: MgBr2 is made from the metal magnesium and the non-metal bromine
It gets named magnesium bromide
Ex: sodium chloride NaCl (one Na and one Cl)
Ex: calcium flouride CaF2 (one Ca, two F)
Ex: aluminium oxide Al2O3 (two Al, three O)
N3- : -3, -3 = -6
Cl - : -1, -1, -1 = - 3