Question

The silver jewellery become dull after prongled use

Answer 1

When silver remains exposed to air for a prolonged period, it gets oxidized and a layer of silver sulphide develops over it and it becomes dull.

Answer 2

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......!!!