Question

Why does the concentration of the electrolyte remain constant during electroplating?

Answer 1

• Electroplating is a method in which the desired metal is plated on another metal with the help of electrolysis.
• For example - Copper metal is to be plated on a second metal.
• The cell includes Copper sulfate $\left({\mathrm{CuSO}}_4\right)$ solution as the electrolyte and a strip of copper that acts as the anode. Here the metal on which Copper will be plated acts as the cathode.
• When the current is applied, copper metal from the anode is oxidized forming cations that enter the electrolyte.
  Anode - $\mathrm{Cu}\left(\mathrm{s}\right)\to {\mathrm{Cu}}^{2+}\left(\mathrm{aq}\right)+2{\mathrm{e}}^{-}$
• These cations that entered the electrolyte undergo reduction and form Copper metal and get deposited on the surface of the cathode i.e., on the second metal. Cathode - ${\mathrm{Cu}}^{2+}\left(\mathrm{aq}\right)+2{\mathrm{e}}^{-}\to \mathrm{Cu}\left(\mathrm{s}\right)$
• Here the cations which enter the solution after oxidation undergo reduction and form the Copper metal and get accumulated on the surface of the second metal.
• The cations which are developed at the anode are utilized at the cathode.
• Hence, the concentration of the electrolyte in the solution remains constant.