hydroselenide

Hydroselenide is a chemical compound with the formula HSe. It is the conjugate acid of the hydroselenide anion (SeH⁻) and is structurally analogous to water (H₂O) and hydrogen sulfide (H₂S). Hydroselenide is a colorless gas that is highly toxic and has a strong, unpleasant odor, similar to rotten eggs. It is often encountered as a component of impure hydrogen gas.

This compound is unstable and readily decomposes. It is soluble in water, forming a weak acidic solution due to the formation of the hydroselenide ion. Hydroselenide can be prepared by the reaction of selenium with hydrogen under specific conditions, or by the acidification of selenide salts. Its properties are similar to hydrogen sulfide, but it is generally more reactive and its compounds tend to be less stable.

The hydroselenide ion (SeH⁻) is the corresponding anion, formed when hydroselenide loses a proton. This ion is also a component in various selenium-containing compounds and plays a role in some chemical reactions. Due to its toxicity and reactivity, hydroselenide and its related compounds require careful handling and are typically studied in controlled laboratory environments. Its applications are limited, primarily existing in research contexts rather than widespread industrial use.