Question

Write the electrode reactions involved in the electrolytic method of preparation of sodium hydroxide

Answer 1

Reaction at cathode

2Na+ +2 e- ==> 2Na

(Na forms amalgam)

Na + Hg ===> Na/Hg

Na+ ions are discharged in preference to H+ ions due to high over voltage.

Reaction at anode

2Cl- ===
Cl2 + 2e-


2Na/Hg + 2H2O ==> 2NaOH + H2 + 2Hg

Answer 2

Answer:

Reaction at cathode

2Na+ +2 e- ==> 2Na

(Na forms amalgam)

Na + Hg ===> Na/Hg

Na+ ions are discharged in preference to H+ ions due to high over voltage.

Reaction at anode

2Cl- ===

Cl2 + 2e-

2Na/Hg + 2H2O ==> 2NaOH + H2 + 2Hg

Explanation: