The sulfide anion is S2-
The chemical formula for aluminum sulfide is Al2S3.
The chemical formula for hydrogen sulfide is H2S.
The ion is S2-.
Sodium sulfide
The chemical symbol for Potassium Sulphate is K2SO4
Mg2+S2-
Iodine is a chemical element with the symbol I and atomic number of 53. It is not considered a mineral sulfide.
The chemical formula (not symbol) of sodium sulfide is Na2S.
The chemical formula for hydrogen sulphide is H2S. (Compounds have chemical formulas; only chemical elements have chemical symbols.)
Ca is the periodic symbol for Calcium. S is the periodic symbol for Sulfur. As such, CaS2 is a compound of calcium and sulfur.
Ni is the symbol for Nickel.
The chemical formula of calcium sulfide is CaS; the ions are Ca2+ and S2-.