Question

Aqueous Solution of ${\mathrm{Na}}_2{\mathrm{S}}_2{\mathrm{O}}_3$ on reaction with ${\mathrm{Cl}}_2$ gives:

• A. $\mathrm{NaCl}$
• B. ${\mathrm{NaHSO}}_4$
• C. $\mathrm{NaOH}$
• D. None of these

Answer 1

The correct option is B

${\mathrm{NaHSO}}_4$

Explanation for correct option:

B. ${\mathrm{NaHSO}}_4$

Reaction of Sodium thiosulfate with chlorine:

• When Sodium thiosulphate $\left({\mathrm{Na}}_2{\mathrm{S}}_2{\mathrm{O}}_3\right)$ reacts with chlorine $\left({\mathrm{Cl}}_2\right)$ gas, it produces Sodium hydrogen sulfate$\left({\mathrm{NaHSO}}_4\right)$ along with Hydrochloric acid$\left(\mathrm{HCl}\right)$.
• The chemical reaction can be depicted as:

${\mathrm{Na}}_2{\mathrm{S}}_2{\mathrm{O}}_3\left(\mathrm{aq}\right)+4{\mathrm{Cl}}_2\left(\mathrm{g}\right)+5{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)\to 2{\mathrm{NaHSO}}_4\left(\mathrm{aq}\right)+8\mathrm{HCl}\left(\mathrm{aq}\right)$

Explanation for incorrect options:

The reaction of Sodium thiosulfate with chlorine produces sodium hydrogen sulfate. thus options A, C and D are incorrect.

Hence, the correct option is B i.e. ${\mathrm{NaHSO}}_4$.