colorless, very poisonous, flammable Hydrogen sulfide is slightly heavier than air; a mixture of H2S and air is explosive. Hydrogen sulfide and oxygen burn with blue flame to form sulfur dioxide (SO2) and water. In general, it acts as a reducing agent.
At high heat or in the presence of catalysts, sulfur dioxide can be made to react with hydrogen sulfide to form elemental sulfur and water. This is exploited in the Claus process, the main way to convert hydrogen sulfide into elemental sulfur.
SOLUTION