9701 MCQ Solution 18

Question 18: [Physical > Electrochemistry]:

In the industrial electrolysis of brine to manufacture chlorine, the diaphragm used is a porous screen which allows the flow of electrolytes but keeps other chemicals separate.

Which substance needs to be kept separate from the chlorine by the diaphragm?

A hydrogen

B sodium hydroxide

C sodium chloride

D water

Reference: Past Exam Paper – November 2002 Paper 1 Q13

Solution 18:

Answer: B.

Sodium hydroxide needs to be separated since it is the only choice that can react with the chlorine formed.