Question

(a) Copy and complete the following table, which refers to two practical applications of electrolysis.

	Anode	Electrolyte	Cathode
(i) Silver plating of a spoon		A solution of potassium argentocyanide
(ii) Purification of copper
(iii) Extraction of sodium

(b) Write the equation taking place at the anode for Q. (a).

Answer 1

(a)

	Anode	Electrolyte	Cathode
(i) Silver plating of a spoon	The plate of pure, clean silver	The solution of potassium argentocyanide	Article to be electroplated
(ii) Purification of copper	Impure copper	The solution of copper sulphate and dilute sulphuric acid	The thin strip of pure copper
(iii) Extraction of sodium	Nickel, Graphite	Fused sodium chloride	Iron

(b) 

1. \[\ce{Ag - e^- -> Ag^+}\]
2. \[\ce{Cu - 2e^- -> Cu^{2+}}\]
3. \[\ce{Cl^- - e^- -> Cl}\]
4. \[\ce{Cl + Cl -> Cl2}\]