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Question
Silver articles become black on prolonged exposure to air. This is due to the formation of
Options
Ag3N
Ag2O
Ag2S
Ag2S and Ag3N
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Solution
Ag2S
Explanation -
Silver objects corrode slowly in the air due to the presence of hydrogen sulphide which reacts with silver articles to form a black coloured chemical compound silver sulphide.
`4"Ag"("s") + 2"H"_2"S"("g") + "O"_2("g") -> 2"Ag"_2"S"("s") + 2"H"_2"O"("l")`
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