Hidrogénszulfit

Hidrogénszulfit is a chemical compound with the formula HSO3-. It is the conjugate base of sulfurous acid (H2SO3) and the conjugate acid of the sulfite ion (SO32-). In aqueous solutions, it exists in equilibrium with sulfurous acid and sulfite ions. The bisulfite ion is a weak acid, with a pKa of approximately 1.81. It is a key species in the chemistry of sulfur dioxide in water, where SO2 dissolves to form H2SO3, which then dissociates to form H+ and HSO3-.

Hidrogénszulfit plays a significant role in various natural and industrial processes. In the environment, it is involved in acid rain formation and the sulfur cycle. Industrially, it is used as a reducing agent, a bleaching agent, and a preservative. For example, in the food industry, bisulfite compounds are sometimes added to dried fruits and wines to prevent oxidation and discoloration. However, their use is regulated due to potential allergic reactions in sensitive individuals.

The salts of hidrogénszulfit are known as bisulfites, such as sodium bisulfite (NaHSO3) and potassium bisulfite (KHSO3). These salts are soluble in water and are often the form in which bisulfite is handled and utilized. The chemistry of hidrogénszulfit is closely related to that of sulfites and sulfur dioxide, and understanding these interrelationships is crucial for comprehending many chemical phenomena.