In a first order reaction,$60 \%$ of the reactant converts into product in $45 \ minutes$. Calculate the rate constant of the reaction.

In a reaction $A + B \rightarrow C$,initial concentrations of $A$ and $B$ are related as $[A]_0 = 8[B]_0$. The half-lives of $A$ and $B$ are $10 \ min$ and $40 \ min$,respectively. If they start to disappear at the same time,both following first-order kinetics,after how much time will the concentration of both the reactants be the same (in $min$)?

For a first-order reaction,the half-life period is $6 \ min$. Find the rate constant of the reaction. (in $min^{-1}$)

$N_2O_5$ decomposes to $NO_2$ and $O_2$ and follows first order kinetics. After $50 \, min$,the pressure inside the vessel increases from $50 \, mm \, Hg$ to $87.5 \, mm \, Hg$. The pressure of the gaseous mixture after $100 \, min$ at constant temperature will be ........... $mm \, Hg$

$A$ reaction has a half-life of $1 \, \text{min}$. The time required for $99.9 \, \%$ completion of the reaction is ......... $\text{min}$. (Round off to the nearest integer)
[Use: $\ln 2 = 0.69, \ln 10 = 2.3$]

Half-life period of a first-order reaction is $10 \ min$. Starting with an initial concentration of $12 \ M$,the rate after $20 \ min$ is: