Mechanism of a hypothetical reaction $X_2 + Y_2 \rightarrow 2XY$ is given below:
$(i)$ $X_2 \rightarrow X + X$ (fast)
$(ii)$ $X + Y_2 \rightleftharpoons XY + Y$ (slow)
$(iii)$ $X + Y \rightarrow XY$ (fast)
The overall order of the reaction will be

For the reaction between $A$ and $B$,the initial rate of reaction $(r_0)$ was measured for different initial concentrations of $A$ and $B$ as given below. Determine the order of the reaction with respect to $A$ and $B$ respectively.

$[A] / mol \ L^{-1}$	$0.2, 0.2, 0.4$
$[B] / mol \ L^{-1}$	$0.3, 0.1, 0.05$
$r_0 / mol \ L^{-1} s^{-1}$	$5.0 \times 10^{-5}, 5.0 \times 10^{-5}, 1.4 \times 10^{-4}$

Consider the reaction between chlorine and nitric oxide:
$Cl_{2(g)} + 2NO_{(g)} \rightarrow 2NOCl_{(g)}$
On doubling the concentration of both reactants,the rate of the reaction increases by a factor of $8$. However,if only the concentration of $Cl_2$ is doubled,the rate increases by a factor of $2$. The order of this reaction with respect to $NO$ is :

For a reaction $A + B \to$ product,it was found that the rate of reaction increases four times if the concentration of $A$ is doubled,but the rate of reaction remains unaffected if the concentration of $B$ is doubled. Hence,the rate law for the reaction is

Why is the hydrolysis of an ester slow at the beginning and fast after some time?

The rate law expression for the reaction $aA + bB \to P$ is $\text{rate} = K [A]^p [B]^q$. The order of the reaction is