For a first-order reaction $A \rightarrow \text{Product}$,the rate of reaction is $1 \times 10^{-2} \, \text{mol L}^{-1} \text{min}^{-1}$ when $[A] = 0.2 \, \text{M}$. What is the half-life $(t_{1/2})$ of the reaction?

$t_{87.5}$ is the time required for the reaction to undergo $87.5 \%$ completion and $t_{50}$ is the time required for the reaction to undergo $50 \%$ completion. The relation between $t_{87.5}$ and $t_{50}$ for a first order reaction is $t_{87.5} = x \times t_{50}$. The value of $x$ is $......$. (Nearest integer)

The rate constant and half-life of a first-order reaction are related to each other as -

$A$ flask contains a mixture of compounds $AB$ and $XY$. Both decompose by first-order kinetics upon heating. If the half-life periods of $AB$ and $XY$ are $30 \ min$ and $10 \ min$ respectively,how many minutes will it take for the concentration of $AB$ to be four times the concentration of $XY$? (Assume initial concentrations of $AB$ and $XY$ are equal.)

Show that in a first order reaction,the time required for completion of $99.9 \%$ is $10$ times the half-life $(t_{1/2})$ of the reaction.

Calculate the rate constant of the first order reaction if $80 \%$ of the reactant decomposes in $60 \ minutes$.