Question

Hydrogentaion of vegetable ghee at ${25}^{o}C$ reduces the pressure of $H_2$ from 2 atm to 1.2 atm in 50 minute. The rate of reaction in terms of change of molarity per second is:

• A. $1.09\times {10}^{-5}mollitr{e}^{-1}se{c}^{-1}$
• B. $2.90\times {10}^{-5}mollitr{e}^{-1}se{c}^{-1}$
• C. $3.29\times {10}^{-5}mollitr{e}^{-1}se{c}^{-1}$
• D. None of these

Answer 1

The correct option is A $1.09\times {10}^{-5}mollitr{e}^{-1}se{c}^{-1}$

$\because PV=nRT$

or $\frac{n}{V}=\frac{P}{RT}=\frac{0.8}{0.0821\times 298}=0.0327m/L$

$\therefore$ Change in molarity $=0.0327mollitr{e}^{-1}$ during 50 minutes

$\therefore$ Rate of reaction $=\frac{\text{Change in pressure}}{\text{Time in minute}}=\frac{0.0327}{50\times 60}$

$=1.09\times {10}^{-5}mol{L}^{-1}se{c}^{-1}$

Hence, the correct option is $A$