Precipitation and Uses of Silver

The solution containing sodium argento cyanide is filtered to remove insoluble impurities and filtrate is treated with zinc dust, silver gets precipitated.

2Na [Ag(CN)2] + Zn → Na2[Zn(CN)4] + 2Ag↓

Electrolytic refining

The impure silver is further purified by electrolytic refining. The impure silver is made the anode while a thin sheet of pure silver act as the cathode. The electrolyte is silvernitrate acidified with 1% nitric acid. On passing electricity pure silver gets deposited at the cathode.

Uses of silver

i) Silver salts are used in silvering of mirrors

ii) AgBr is used in photography

iii) Silver salts are used in silver plating.

iv) Silver is used in making electrodes.

v) Silver leaf is used in medicine, while silver amalgam is employed in dental filling.