For the first order reaction with rate constant $k$,which expression gives the half-life period? (Initial concentration $= a$)

Decomposition of $H_2O_2$ follows a first order reaction. In $50 \ min$,the concentration of $H_2O_2$ decreases from $0.5 \ M$ to $0.125 \ M$. For such decomposition,when the concentration of $H_2O_2$ reaches $0.05 \ M$,the rate of formation of $O_2$ will be:

Which of the following plots is(are) correct for the given reaction? $( [P]_0$ is the initial concentration of $P$ $)$

The time required for a first-order reaction to be $90\%$ complete is approximately .........

The following data were obtained during the first order thermal decomposition of a gas $A$ at constant volume:
$A_{(g)} \rightarrow 2 B_{(g)} + C_{(g)}$

$S.No.$	$Time/s$	$Total Pressure/(atm)$
$1.$	$0$	$0.1$
$2.$	$115$	$0.28$

The rate constant of the reaction is . . . . . . $\times 10^{-2} \ s^{-1}$ (nearest integer).

$A ( g ) \rightarrow 2 B ( g ) + C ( g )$ is a first order reaction. The initial pressure of the system was found to be $800 \ mm \ Hg$ which increased to $1600 \ mm \ Hg$ after $10 \ min$. The total pressure of the system after $30 \ min$ will be . . . . . . $mm \ Hg$. (Nearest integer)