For a reaction $A \rightarrow$ products,the half-life period is $1 \ h$. The initial concentration of reactant $A$ is $2 \ M$. If this reaction is of zero order,how many hours will it take for the concentration of the reactant to decrease from $0.5 \ M$ to $0.25 \ M$?

The rates of a certain reaction $(dc/dt)$ at different times are as follows:

Time $(sec)$	Rate $(mole \ litre^{-1} \ sec^{-1})$
$0$	$2.8 \times 10^{-2}$
$10$	$2.78 \times 10^{-2}$
$20$	$2.81 \times 10^{-2}$
$30$	$2.79 \times 10^{-2}$

The reaction is:

The half-life period of a zero order reaction is:

In which one of the following reactions,the rate constant has the unit $mol \ L^{-1} \ s^{-1}$?

For the reaction $R \rightarrow P$,the concentration of $R$ is measured as a function of time and the following data is obtained:

$[R] \ (M)$	$1.0$	$0.76$	$0.40$	$0.10$
$t \ (min)$	$0.0$	$0.05$	$0.12$	$0.18$

The order of the reaction is:

For a reaction of $n^{th}$ order,the plot of $t_{1/2}$ versus initial concentration $[A]_0$ is a straight line. When the initial concentration is $2 \ mol \ L^{-1}$,the reaction takes $10 \ min$ to complete $50\%$. If the reaction takes $t \ min$ to complete $50\%$ when the initial concentration is $4 \ mol \ L^{-1}$,find $n$ and $t$ respectively.