Question

Which metal becomes black in the presence of hydrogen sulphide gas in air?

Answer 1

Silver metal becomes black in the presence of hydrogen sulphide gas in the air. Silver reacts with hydrogen sulphide gas in the air and forms a thin black layer of silver sulphide $\left(A{g}_{2}S\right)$ on it. Therefore, silver jewellery or ornaments become dull due to the formation of silver sulphide coating on their surface.