JEE Main201910 Jan 2019Evening ShiftChemistryGeneral Principles and Processes of Isolation of MetalsActual
The electrolytes usually used in the electroplating of gold and silver, respectively, are:
Options
- AAu NH 3 2 + and Ag CN 2 -
- BAu CN 2 - and AgCl 2 -
- CAu OH 4 - and Ag OH 2 -
- DAu CN 2 - and Ag CN 2 -
Correct answer
D. Au CN 2 - and Ag CN 2 -
Step-by-step 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.