Question

Calculate the quantity of electricity that would be required to reduce 12.3 g of nitrobenzene to aniline, if current efficiency is 50% if the potential drops across the cell are 3.0 volt, how much energy will be consumed?

• A. 347.4 kJ
• B. 152.7 kJ
• C. 273.2 kJ
• D. 173.7 kJ

Answer 1

The correct option is A 347.4 kJ

The reduction of Nitrobenzene can be written as

$C_6{H}_{5}N{O}_2+6H^{+}+6e^{-}\to C_6{H}_{5}N{H}_2+2H_{2}O$

The molar mass of Nitrobenzene = 123g

123 gm of Nitrobenzene use 6 mol electrons for complete reaction

12.3 gm of Nitrobenzene will use 0.6 mol electrons for complete reaction

0.6 mole electron $=0.6\times 96500=57900$ C

Efficiency is $50\%$

Required charge $=57900\times 2=115800$ C

Energy $=QV=(115800\times 3)$ J $=347.4$ kJ

Hence, the correct option is $\text{A}$