tinII

Tin(II) refers to tin in the +2 oxidation state, written as Sn2+. It is commonly called stannous and is one of the two stable oxidation states of tin, the other being tin(IV) (Sn4+). Tin(II) occurs in a range of compounds, with the most familiar being stannous chloride (SnCl2), stannous fluoride (SnF2), and stannous sulfate (SnSO4). Tin(II) oxide (SnO) is also known, though it is less stable in air and can convert to tin(IV) compounds upon exposure to oxygen.

Properties of tin(II) are influenced by its electronic structure, including a stereochemically active lone pair that can lead to covalent character and distortions in crystal lattices. In redox chemistry, Sn2+ is a mild reducing agent and is readily oxidized by oxidants such as oxygen to tin(IV) species. In aqueous media, tin(II) salts can hydrolyze to form tin hydroxide species, with stability strongly dependent on pH and ligand environment. Tin(II) compounds tend to be soft Lewis acids and form complexes with ligands such as chloride, cyanide, or various organic ligands.

Applications of tin(II) compounds include use as reducing agents in chemical synthesis, precursors to other tin-containing materials, and various industrial roles such as plating and catalysis. Stannous chloride, in particular, has historical uses in analytical chemistry and photography, and tin(II) salts continue to find specialized uses in research contexts.

Safety and handling: tin(II) compounds can be irritants and may pose environmental and health risks if mishandled. Proper precautions and containment are advised when working with tin(II) reagents.