Question

If the volume of the vessel in which the reaction $2NO+O_2⟶{2NO}_2$ is occurring is diminished to 1/3rd of its initial volume. The rate of the reaction will be increased by:

• A. 3 times
• B. 9 times
• C. 27 times
• D. 36 times

Answer 1

The correct option is C 27 times

As we know that, rate of reaction is directly proportional to concentration of reactant and inversely proportional to the volume of vessel.

ie, rate $\propto \frac{n}{V}$

For a given reaction,

$2NO\left(g\right)+O_2\left(g\right)\rightleftharpoons 2{NO}_2\left(g\right)$

Rate of reaction $={k\left[NO\right]}^2\left[O_2\right]$

If the volume of the vessel is reduced by $\frac{1}{3}$rd of its initial value, then the concentration of reactant is increased by 3 times.

Rate of reaction $=k(3\left[NO\right]{)}^2\left(3\left[O_2\right]\right)=27{k\left[NO\right]}^2\left[O_2\right]$

Hence, the rate of reaction will be increased by 27 times.