Sulfidi

Sulfidi are chemical compounds that contain sulfur in its lowest oxidation state, typically -2. They can be formed between sulfur and a more electropositive element. Inorganic sulfidi are commonly found as minerals, such as pyrite (iron sulfide) and galena (lead sulfide). Many metal ions readily precipitate as insoluble sulfidi when exposed to hydrogen sulfide gas or soluble sulfide salts. These precipitation reactions are often used in qualitative inorganic analysis to identify different metal ions. Organic sulfidi, also known as thioethers, are characterized by the presence of a sulfur atom bonded to two organic groups. They play important roles in biochemistry, for example, in the amino acid methionine. Some sulfidi are volatile and have strong, often unpleasant odors, such as hydrogen sulfide (H2S), which smells like rotten eggs. Sulfidi are important in various industrial processes, including metallurgy and petroleum refining.