Question

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

• A. $\left[Au\right(OH{)}_4{]}^{-}and\left[Ag\right(OH{)}_2{]}^{-}$
• B. $\left[Au\right(CN{)}_2{]}^{-}and\left[Ag\right(c{l}_2{]}^{-}$
• C. $\left[Au\right(NH{)}_3{)}_2{]}^{+}and\left[Ag\right(CN{)}_2{]}^{-}$
• D. $\left[Au\right(CN{)}_2{]}^{-}and\left[Ag\right(CN{)}_2{]}^{-}$

Answer 1

The correct option is D $\left[Au\right(CN{)}_2{]}^{-}and\left[Ag\right(CN{)}_2{]}^{-}$

The Anode is a bar of silver metal, and the electrolyte (the liquid in between the electrodes) is a solution of Silver cyanide, ${\left[Ag{\left(CN\right)}_2\right]}^{-}$, in water.

Gold plating is done in much the same way, using a gold anode and an electrolyte containing Gold cyanide, ${\left[Au{\left(CN\right)}_2\right]}^{-}$.

Option D is correct