"-ate" is used for the salt of the higher oxidation state of the element and "ite" for the salt of the next lower oxidation state. sulfate has the formula SO4-2 and "sulfite" has the formula SO3-2, with sulfur having an oxidation state of +6 in sulfate and +4 in sulfite.
Sulphide is S(-2), Sulphite is SO3(-1), while Sulphate is SO4(-2). On the other hand, sulphide and sulphite belong to dilute acid group while sulphate is a special group radical. By adding dilute H2SO4, Sulphide gives out H2S gas and Sulphite gives out SO2 gas while Sulphate has very less reactivity.
Sulfates are mineral salts containing sulfur. While Sulfites are different sulfur-containing chemicals