Question

The quantity of electricity required to reduce $12.3\mathrm{g}$ of nitro benzene to aniline assuming $50\%$ current efficiency is

• A. $115800\mathrm{C}$
• B. $28950\mathrm{C}$
• C. $231600\mathrm{C}$
• D. $57900\mathrm{C}$

Answer 1

The correct option is A

$115800\mathrm{C}$

Explanation for correct option:

(A) $115800\mathrm{C}$

Step 1: Reduction of nitro benzene:

• Reaction for reduction :

${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{NO}}_2\left(\mathrm{aq}\right)+6{\mathrm{H}}^{+}\left(\mathrm{aq}\right)+6{\mathrm{e}}^{-}⟶{\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{NH}}_2\left(\mathrm{aq}\right)+2{\mathrm{H}}_2\mathrm{O}\left(\mathrm{l}\right)$

Step 2: Molar mass of nitrobenzene:

• Given, the molar mass of ${\mathrm{C}}_6{\mathrm{H}}_5{\mathrm{NO}}_2=123$
• Here,$12.3\mathrm{g}$ nitrobenzene mole $=1236\times 12.3$

$=0.6$

Step 3: Calculating the charge required:

$$\begin{gathered} \mathrm{charge}=0.6\times 96500\mathrm{coloumbs} \\ =57900\mathrm{C} \end{gathered}$$

$$\begin{gathered} \mathrm{Efficiency}=50\%\Rightarrow 2\times 57900\mathrm{coloumbs} \\ =115800\mathrm{coloumbs} \\ \therefore \mathrm{charge}\mathrm{required}\mathrm{is}115800\mathrm{coloumbs}. \end{gathered}$$

This is the correct option.

Explanation for incorrect options:

Since, the correct answer is $115800\mathrm{C}$. Therefore, options (B), (C) and (D) stand incorrect.

Therefore, the correct option is (A) $115800\mathrm{C}$.