Q14 / 90 · JEE Main 2019 (10 Jan Shift 2) · Chemistry

The electrolytes usually used in the electroplating of gold and silver, respectively, are:

A
${[Au {({NH}_{3})}_{2}]}^{+}$ and ${[Ag {(CN)}_{2}]}^{-}$
B
${[Au {(CN)}_{2}]}^{-}$ and ${[{AgCl}_{2}]}^{-}$
C
${[Au {(OH)}_{4}]}^{-}$ and ${[Ag {(OH)}_{2}]}^{-}$
Correct answer
D
${[Au {(CN)}_{2}]}^{-}$ and ${[Ag {(CN)}_{2}]}^{-}$

Solution

The solution of dicyano complexes of gold $(Au)$ and silver $(Ag)$ are used as electrolytes while performing electroplating with them.
The amine complexes of gold are not stable, so, they cannot be used.
Silver cyanide is employed as cyanide reacts with silver to form stable complexes.

Hence, the correct answer is option: 'D'.

Relevant Questions