Question

In an acidic medium, the rate of reaction between $\left(Br{O}_3^{\ominus }\right)$ and $B{r}^{\ominus }$ ions is given by the expression
$\frac{-d[Br{O}_3^{\ominus }}{dt}=k\left[Br{O}_3^{\ominus }\right]\left[B{r}^{\ominus }\right][H^{\oplus }{]}^2$
It means :

• A. The rate constant of overall reaction is $4s^{-1}$
• B. The rate of reaction is independent of the concentration of acid.
• C. The change in pH of the solution will not affect the rate.
• D. Doubling the concentration of $H^{\oplus }$ ions will increase the reaction rate by 4 times.

Answer 1

The correct option is D Doubling the concentration of $H^{\oplus }$ ions will increase the reaction rate by 4 times.

$\frac{-d[Br{O}_3^{\ominus }}{dt}=k\left[Br{O}_3^{\ominus }\right]\left[B{r}^{\ominus }\right][H^{\oplus }{]}^2$
Order w.r.t. $\left[H^{\oplus }\right]=2$
Hence, doubling the concentration of $\left[H^{\oplus }\right]$ ions will increase the reaction rate by 4 times.