What is the IUPAC name for CaSO4?

The IUPAC name for CaSO4 is Calcium sulfate. This name is derived from the systematic rules of chemical nomenclature established by the International Union of Pure and Applied Chemistry (IUPAC).

In this compound, calcium (Ca) is a metal that has a +2 oxidation state, while the sulfate ion (SO4) carries a -2 charge. The naming convention specifies that the name of the metal is stated first, followed by the name of the polyatomic ion.

Sulfate refers specifically to the SO4 ion, which is a well-defined polyatomic ion consisting of one sulfur atom covalently bonded to four oxygen atoms. The name uses the suffix "-ate," indicating that it is one of the most common oxidation states of sulfur in its oxoanions.

Other options presented do not correspond to the correct systematic naming. For example, "Calcium sulfite" refers to CaSO3, which contains a different number of oxygen atoms. "Calcium salt" is too vague and does not specify the species involved. "Sulfate calcium" reverses the proper order of naming, which goes against IUPAC conventions that require stating the cation (metal) first followed by the anion (polyatomic ion