Question

For the reaction system $2NO\left(g\right)+O_{2}\left(g\right)\to2NO\left(g\right)$ volume is suddenly produced to half its value by increasing the pressure on it. If the reaction is of first order with respect to $O_2$ and second order with respect to $NO,$ the rate of reaction will

• A. Diminish to one fourth of its initial value
• B. Diminish to one eighth of its initial value
• C. Increase to eight times of its initial value
• D. Increase to four times of its initial value

Answer 1

Answer: (C)

$R=k\left[NO\right]^{2}\left[O_{2}\right],R=k\left[2NO\right]^{2}\left[2O_{2}\right]$
$R=k\times4\left[NO\right]^{2}\left[O_{2}\right]=k\times8\left[NO\right]^{2}\left[O_{2}\right]$
$\frac{R'}{R}=\frac{k\times8\left[NO\right]^{2}\left[O_{2}\right]}{k\left[NO\right]^{2}\left[O_{2}\right]}=8$