Silver articles become black when kept in open for some time, whereas copper vessels lose their shiny brown surfaces and gain a green coat when kept in open. Name the substances present in air with which these metals react and write the name of the products formed.
Silver articles become black when kept in open for some time, whereas copper vessel loses their shiny brown surfaces and gain a green coat when kept in open because silver articles react with sulphur compounds such as hydrogen sulphide present in the air to form black silver sulphide (Ag2S) whereas copper reacts slowly with carbon dioxide (CO2 ) and water present in the air to form a green coating of a mixture of copper carbonate and copper hydroxide.
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