Question

When electricity is passed through brine solution:

• A. gas given out at anode burns with a pop sound.
• B. gas given out at cathode burns with a pop sound.
• C. gas given out at anode is used for making bleaching powder.
• D. gas given out at cathode is used for making bleaching powder.

Answer 1

Answer: (B), (C)

The correct options are
B gas given out at cathode burns with a pop sound.
C gas given out at anode is used for making bleaching powder.

Aqueous solution of sodium chloride is called brine. When electricity is passed through brine solution, the following reaction takes place:

$2\mathrm{NaCl}\left(\mathrm{aq}\right)+2H_{2}O\left(l\right)\to 2\mathrm{NaOH}\left(\mathrm{aq}\right)+{\mathrm{Cl}}_2\left(g\right)+H_2\left(g\right)$

Chlorine gas is given out at anode and hydrogen gas given out at the cathode.

The chlorine produced is used for the manufacture of bleaching powder. (${\text{CaOCl}}_2$)

$\mathrm{Ca}(\mathrm{OH}{)}_2\left(\mathrm{aq}\right)+{\mathrm{Cl}}_2(\mathrm{aq})\to {\mathrm{CaOCl}}_2(\mathrm{aq})+H_{2}O(l)$

The hydrogen gas burns a matchstick with a pop sound.