Silver articles turn black when kept in the open for longer time due to the formation of
H₂S
AgS
AgSO₄
Ag₂S
Answer is Right!
Answer is Wrong!
This question was previously asked in
UPSC CDS-2 – 2020
Silver articles tarnish and turn black when exposed to the air for a prolonged period. This tarnishing is primarily due to the reaction of silver (Ag) with hydrogen sulfide (H₂S) gas present in the atmosphere (often produced by the decomposition of organic matter or industrial pollution). This reaction forms a layer of black silver sulfide (Ag₂S) on the surface of the silver article. The overall reaction is 2Ag + H₂S → Ag₂S + H₂.
Silver tarnish is caused by the formation of silver sulfide (Ag₂S) through the reaction of silver with hydrogen sulfide in the air.