Question

$\mathrm{NaOH}$can be prepared by the electrolysis of molten $\mathrm{NaCl}.$

• A. True
• B. False

Answer 1

The correct option is A True

Electrolysis of molten NaCl:

• When an electric current is passed through a concentrated brine solution (aqueous solution of Sodium chloride), Sodium chloride $\left(\mathrm{NaCl}\right)$ decomposes to form Sodium hydroxide $\left(\mathrm{NaOH}\right)$ near the cathode.
• The other products are Chlorine gas $\left({\mathrm{Cl}}_2\right)$ and Hydrogen gas $\left({\mathrm{H}}_2\right).$
• This process of producing Sodium hydroxide $\left(\mathrm{NaOH}\right)$ from Sodium chloride $\left(\mathrm{NaCl}\right)$ is called the Chlor-alkali process, where chlor is for Chlorine and alkali is for Sodium hydroxide.
• $\underset{(\mathrm{Sodium}\mathrm{chloride})}{2\mathrm{NaCl}\left(\mathrm{aq}\right)}+\underset{\left(\mathrm{Water}\right)}{2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)}\to \underset{(\mathrm{Sodium}\mathrm{hydroxide})}{2\mathrm{NaOH}\left(\mathrm{aq}\right)}+\underset{(\mathrm{Chlorine}\mathrm{gas})}{{\mathrm{Cl}}_2\left(\mathrm{g}\right)\uparrow }+\underset{(\mathrm{Hydrogen}\mathrm{gas})}{{\mathrm{H}}_2\left(\mathrm{g}\right)\uparrow }$
• Here Chlorine is obtained at the anode and hydrogen at the cathode.

Hence $\mathrm{NaOH}$ can be prepared from the electrolysis of $\mathrm{NaCl}.$

Therefore, the statement is true.