Question

Calculate the quantity of electricity that would be required to reduce 12.3 g of nitrobenzene to aniline if the current efficiency for the process is 50 per cent.If the potential drop across the cell is 3 volts, how much energy will be consumed ?​

Answer 1

Answer :

• Quantity of electricity required = 115800 C.
• Energy consumed = 347400 J.

Step-by-step explanation :

Given that,

• Current efficiency = 50%
• Potential drop = 3 volts.

Also,

• Molar mass of nitrobenzene = 123 g/mol.

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The reduction reaction may be written as follows :-

$\rm{C_6H_5NO_2+6H^++6\:e^-\longrightarrow{}C_6H_5NH_2+2H_2O}$

Thus, 1 mol of $\rm{C_6H_5NO_2}$, i.e., 123 g require electricity = 6 × 96500 C = 579000 C

∴ 12.3 g require electricity = 57900 C

Now, as the current efficiency is 50%, quantity of electricity actually required

= 2 × 57900 C = 115800 C

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Energy consumed = EMF × Quantity of electricity

= 3 × 115800 J = 347400 J