Give reasons :(i) Silver metal does not easily combine with oxygen but silver jewellary tarnishes after sometime. (ii) Iron grills are frequently painted. (iii) Gold ornaments retain their luster even after several years of use.

Give reasons :(i) Silver metal does not easily combine with oxygen but

1.	Give reasons :(i) Silver metal does not easily combine with oxygen but silver jewellary tarnishes after sometime. (ii) Iron grills are frequently painted. (iii) Gold ornaments retain their luster even after several years of use.
Answer» SOLUTION : (i) Silver metal reacts with the H S GAS present in traces in the atmosphere to form silver SULPHIDE which tarnishes the metal. (ii) Iron forms a layer of RUST `(Fe_2O_3.xH_2O)`on combination with oxygen and moisture present inthe atmosphere. This weakens the metal. To prevent this loss iron grills are frequently painted. (iii) Gold is an unreactive metal. It does not react with atmospheric oxygen and acids. So the lustreof gold jewellery is retained even after SEVERAL years