The half-life of decomposition of gaseous $CH_3CHO$ at initial pressure of $364 \ mm$ and $182 \ mm$ of $Hg$ were $440 \ sec$ and $880 \ sec$ respectively. The order of the reaction is

Define the following terms:
$(1)$ Rate law / Rate equation / Rate expression
$(2)$ Unimolecular reaction

The initial rates of decrease of $I_2$ in acetone-iodine reaction catalysed by $H^{+}$ are given in the table.

Experiment	Initial $[I_2]$ $(mol \ L^{-1})$	Initial $[H^{+}]$ $(mol \ L^{-1})$	Initial $[CH_3COCH_3]$ $(mol \ L^{-1})$	Initial rate $(mol \ L^{-1} \ s^{-1})$
$1$	$0.01$	$0.1$	$0.1$	$0.096$
$2$	$0.01$	$0.2$	$0.1$	$0.192$
$3$	$0.02$	$0.2$	$0.1$	$0.192$
$4$	$0.01$	$0.2$	$0.2$	$0.384$

The order with respect to $I_2, H^{+}$,acetone and total order of the reaction respectively are:

The correct difference between $1^{st}$-order and $2^{nd}$-order reaction is that:

For the reaction $H_{2(g)} + Br_{2(g)} \rightarrow 2HBr_{(g)}$,the experimental data suggests the rate law is $\text{Rate} = K[H_2][Br_2]^{1/2}$. Find the order of the reaction and its molecularity.

The rate law for a reaction between reactants $A$,$B$,and $C$ is $r = K[A][B][C]^2$. If the concentration of $A$ is halved,then the rate of reaction: