The role of copper diaphragm in Whytlaw-Gray's method is

• A

  preventing the corrosion of electrolytic cell
• Correct answer
  B

  preventing the mixing of $\mathrm{H}_2$ and $\mathrm{F}_2$
• C

  as anode
• D

  as cathode

Solution

In Whytlaw-Gray's method for preparation of fluorine, the copper diaphragm is used to prevent the mixing of $\mathrm{H}_2$ and $\mathrm{F}_2$ liberated at cathode and anode respectively. Reactions in the electrolytic cell

Hence, the correct answer is option: 'B'.