Question

Identify the correct representation of the reaction occurring during the chloralkali process

• A. $2\mathrm{NaCl}\left(\mathrm{l}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to 2\mathrm{NaOH}\left(\mathrm{l}\right)+{\mathrm{Cl}}_2\left(\mathrm{g}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right)$
• B. $2\mathrm{NaCl}\left(\mathrm{aq}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{aq}\right)\to 2\mathrm{NaOH}\left(\mathrm{aq}\right)+{\mathrm{Cl}}_2\left(\mathrm{g}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right)$
• C. $2\mathrm{NaCl}\left(\mathrm{aq}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to 2\mathrm{NaOH}\left(\mathrm{aq}\right)+{\mathrm{Cl}}_2\left(\mathrm{aq}\right)+{\mathrm{H}}_2\left(\mathrm{aq}\right)$
• D. $2\mathrm{NaCl}\left(\mathrm{aq}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to 2\mathrm{NaOH}\left(\mathrm{aq}\right)+{\mathrm{Cl}}_2\left(\mathrm{g}\right)+{\mathrm{H}}_2\left(\mathrm{g}\right)$

Answer 1

The correct option is D

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

Explanation:

Chloralkali process:

• The Chlor-alkali process is an industrial process in which on the passing electricity Sodium chloride solution decomposes to Sodium hydroxide along with the evolution of Hydrogen and chlorine at Cathode and anode respectively.
• The balanced chemical reaction of the Chlor-alkali process can be represented as:

$\underset{\mathrm{Brine}\mathrm{solution}}{\underset{\mathrm{Sodium}\mathrm{chloride}}{2\mathrm{NaCl}\left(\mathrm{aq}\right)}+\underset{\mathrm{Water}}{2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}}\stackrel{\mathrm{Electrolysis}}{\to }\underset{\mathrm{Sodium}\mathrm{hydroxide}}{2\mathrm{NaOH}\left(\mathrm{aq}\right)}+\underset{\mathrm{Chlorine}}{\mathrm{C}{\mathrm{l}}_2\left(\mathrm{g}\right)}+\underset{\mathrm{Hydrigen}}{{\mathrm{H}}_2\left(\mathrm{g}\right)}$

• The word ‘Chlor’ stands for chlorine and the word ‘alkali’ is for Sodium hydroxide$\left(\mathrm{NaOH}\right)$, therefore the process is called the chlor-alkali process and is also known as the electrolysis of brine.

Hence, option D is correct.