Chemistry - Chemical Kinetics Question with Solution | TestHub

For the given reaction $A+3B\to 2C$, the rate of reaction is expressed as:

$\text{Rate}=-\frac{d[A]}{dt}=-\frac{1}{3}\frac{d[B]}{dt}=\frac{1}{2}\frac{d[C]}{dt}$

The rate of consumption of $A$ is $-\frac{d[A]}{dt}=1.4{\text{ mol dm}}^{-3}{\text{ min}}^{-1}$.

The rate of consumption of $B$ is $-\frac{d[B]}{dt}$.

From the rate expression:

$-\frac{1}{3}\frac{d[B]}{dt}=-\frac{d[A]}{dt}$

$-\frac{d[B]}{dt}=3\times \left(-\frac{d[A]}{dt}\right)$

$-\frac{d[B]}{dt}=3\times 1.4=4.2{\text{ mol dm}}^{-3}{\text{ min}}^{-1}$

Answer: $4.2\mathrm{mol}{\mathrm{dm}}^{-3}$ minute ${}^{-1}$