sodium hydrosulfide

Sodium hydrosulfide is the chemical compound with the formula NaHS. This compound is the product of the half neutralization of hydrogen sulfide with sodium hydroxide. NaHS is a useful reagent for the synthesis of organic and inorganic sulfur compounds, sometimes as a solid reagent, and more often as an aqueous solution. Solid NaHS is colorless and typically smells like H₂S due to hydrolysis by atmospheric moisture. In contrast with sodium sulfide, Na₂S, which is insoluble in organic solvents, NaHS, being a 1:1 electrolyte, is more soluble. Alternatively, in place of NaHS, H₂S can be treated with an organic amine to generate an ammonium salt. Solutions of HS^- are sensitive to oxygen, converting mainly to polysulfides, indicated by the appearance of yellow.