Question

In the electroplating of silver, $AgN{O}_3$ solution is usually used as:

• A. oxidant
• B. reductant
• C. electrode
• D. electrolyte

Answer 1

The correct option is D electrolyte

The process of depositing a thin layer of silver electrolytically on the metal surface is called silver plating. The article to be silver-plated is used as cathode while anode consists of pure silver.

The bath contains a solution of potassium argentocyanide ($AgN{O}_3$ + excess of KCN). The complex ion is very stable and ionisation is very small at a time with the result slow and uniform deposition of silver takes place.

$\left[Ag\right(CN{)}_2{]}^2\rightleftharpoons A{g}^{+}+2C{N}^{-}$

Hence, option D is correct.