bisulfidiioni
Bisulfidiioni is the chemical name for the bisulfide anion, which has the chemical formula HS-. It is the conjugate base of hydrogen sulfide (H2S) and can be formed when hydrogen sulfide loses a proton. In aqueous solutions, the bisulfide ion is in equilibrium with hydrogen sulfide and sulfide ions (S2-). The relative amounts of each species depend on the pH of the solution. At low pH, the equilibrium favors hydrogen sulfide, while at higher pH, the bisulfide and sulfide ions become more prevalent. The bisulfide ion is a weak acid. It is a colorless ion and is soluble in water. It plays a role in various chemical and biological processes, including sulfur cycling in ecosystems. Bisulfide ions can also act as ligands in coordination chemistry, forming complexes with metal ions. Its presence is often associated with environments rich in sulfur compounds, such as hydrothermal vents and anaerobic sediments.