Hydrogen sulfide

Poisonous and flammable gas

Hydrogen sulfide (preferred IUPAC name and American English) or hydrogen sulphide (Commonwealth English) is a chemical compound with the formula H2S. It is a colorless, toxic, and flammable hydrogen chalcogenide gas. Trace amounts in the ambient atmosphere have a characteristic foul odor of rotten eggs. Swedish chemist Carl Wilhelm Scheele is credited with having discovered the chemical composition of purified hydrogen sulfide in 1777.

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