XSO4

XSO4 refers to a family of inorganic salts composed of a divalent metal cation X2+ and the sulfate anion SO4 2-. The exact properties of XSO4 depend on the identity of X. Common examples include MgSO4, CaSO4, ZnSO4, CuSO4, and FeSO4, illustrating the range from highly soluble to sparingly soluble sulfates.

Structure and bonding: XSO4 salts are typically ionic solids formed from X2+ ions and the sulfate anion, which consists of a central sulfur atom surrounded by four oxygen atoms in a tetrahedral arrangement. In the solid state, XSO4 adopts three-dimensional lattices with coordination environments reflecting the size and charge of X.

Synthesis and interconversion: XSO4 can be prepared by reacting the corresponding oxide, hydroxide, or carbonate with sulfuric acid, for example XCO3 + H2SO4 → XSO4 + CO2 + H2O or X(OH)2 + H2SO4 → XSO4 + 2 H2O. Direct reaction of a metal with concentrated sulfuric acid is possible for more reactive metals. Many XSO4 salts also form hydrates, yielding XSO4·nH2O, depending on the metal and environmental conditions.

Physical properties and solubility: Solubility in water varies with X. Alkali and some transition metal sulfates are highly soluble, while many heavier alkaline earth sulfates are less soluble, with BaSO4 and SrSO4 notably insoluble and CaSO4 only sparingly soluble. Hydrated forms are common for several XSO4 salts, especially with smaller cations.

Applications and occurrence: Sulfates are widespread in nature and industry. Gypsum (CaSO4·2H2O) and plaster are well-known minerals and construction materials; magnesium sulfate (MgSO4) finds use in medicine and agriculture; copper sulfate (CuSO4) serves as a fungicide and in electroplating; zinc sulfate is used in agriculture and chemical synthesis. Occurrence ranges from minerals such as gypsum and anhydrite to a variety of synthetic salts in laboratories and industry.

Safety: General handling follows standard inorganic salt precautions. Some sulfates contain toxic or regulatory concern elements; inhalation of dust and ingestion can pose health risks, and disposal should follow local regulations.