(a) Identify the gasses evolved at the anode and cathode in the above experimental set up.
(b) Name the process that occurs. Why is it called so?
(c) Illustrate the reaction of the process with the help of a chemical equation.
(a) Brine is a solution of salt (NaCl) in water.
- When subjected to electrolysis , it separates into its constituent ions , Na+ and Cl-.
- The positive ion is attracted to the cathode (-ve) and Negative is attracted to the anode (+ve).
- H+ ions are also produced and attracted to the cathode .
- Hence, Cl- ions and H+ ions combine to form Cl 2 and H 2 at the anode and cathode respectively and are liberated as gases .
Anode : Chlorine
Cathode : Hydrogen
(b) Chlor alkali process .
The industrial production of Sodium Hydroxide and chlorine by the process of electrolysis of Sodium Chloride Solution is known as the Chlor Alkali Process.
The products obtained are alkali , chlorine gas and hydrogen gas.
(c) 2NaCl(aq) + 2H 2 O(l) 2NaOH(aq) + Cl 2 (g) + H 2 (g)