# The rate of the elementary reaction, $2NO+O_2 \to 2NO_2$ when the volume of the reaction vessel is doubled

$(A)\;\text{will grow eight times of its initial rate} \\ (B)\;\text{Reduce to one-eight of its initial rate } \\(C)\;\text{will grow four times of its initial rate } \\(D)\;\text{Reduce to one- fourth of its initial rate }$

$Rate =K[NO]^2[O_2]^1$
Concentration of each species are reduced by $\large\frac{1}{2}$ on increasing volume to two times and thus rate becomes $\large\frac{1}{8}$ time of initial rate .
Hence b is the correct answer.