Question

For a reaction $A+B\to Products$, it is observed that doubling the concentration of $B$ caused the reaction rate to increase four times, but doubling the concentration of $A$ has no effect on the rate of reaction. The rate equation is therefore:

• A. rate = $K[A{]}^2$
• B. rate = $K[B{]}^2$
• C. rate = $K\left[A\right]\left[B\right]$
• D. rate = $K\left[A\right]$

Answer 1

The correct option is B rate = $K[B{]}^2$

Doubling the conc of $B$ caused the reaction rate to increase four times. So Order wrt $\left[B\right]$ is $2$.

Doubling the conc of $A$ has no effect. So Order wrt $\left[A\right]$ is $0$

The overall rate is,

$rate=K[B{]}^2$