If $a$ is the initial concentration of the reactant,the half-life period of the reaction of $n^{th}$ order is inversely proportional to

The half-lives of two samples are $0.1 \ s$ and $0.4 \ s$. Their respective concentrations are $200$ and $50$. What is the order of the reaction?

The rate constant for a reaction is $10.8 \times 10^{-5} \ mol \ L^{-1} \ s^{-1}$. The order of the reaction is .......

$A$ reaction is of second order with respect to carbon monoxide. If the concentration of carbon monoxide is doubled,keeping everything else constant,the rate of the reaction will...

Reaction : $2Br^{-} + H_2O_2 + 2H^{+} \to Br_2 + 2H_2O$
takes place in two steps :
$(a)$ $Br^{-} + H^{+} + H_2O_2 \xrightarrow{slow} HOBr + H_2O$
$(b)$ $HOBr + Br^{-} + H^{+} \xrightarrow{fast} H_2O + Br_2$
The order of the reaction is

The mechanism of the reaction,$2NO_{(g)} + 2H_{2(g)} \to N_{2(g)} + 2H_2O_{(g)}$ is:
Step $1$: $2NO_{(g)} + H_{2(g)} \xrightarrow{\text{slow}} N_2 + H_2O_2$
Step $2$: $H_2O_2 + H_2 \xrightarrow{\text{fast}} 2H_2O$
Then the correct statement is: