Why Silver articles become black when exposed to air ?

Silver articles become black on exposure to air for sometime. When silver articles exposed to air silver racts with sulphur present in the atmosphere and form a black layer of silver sulphide on the surface.
Silver articles, when exposed to air become black after sometime. This is because the silver metal reacts with sulphur present in the atmosphere and forms silver sulphide. Thus, a layer of silver sulphide is formed on the surface of silver articles, because of which they appear dull and black.