$A$ reaction which is of first order with respect to reactant $A$,has a rate constant $6 \, min^{-1}$. If we start with $[A] = 0.5 \, mol \, L^{-1}$,when would $[A]$ reach the value of $0.05 \, mol \, L^{-1}$?

$t_{87.5}$ 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)

Half-life period of a first order reaction is $1386 \ s$. The specific rate constant of the reaction is

Which of the following graphs has an intercept equal to zero?

The half-life period for a first order reaction is $693 \ sec$. The rate constant for this reaction would be: (in $sec^{-1}$)

Dissociation of $N_2O_5$ dissolved in $CCl_4$ at constant temperature: $N_2O_{5(soln)} \to 2NO_{2(soln)} + \frac{1}{2}O_{2(g)}$. This is a first order reaction. The velocity constant is $5.0 \times 10^{-4} \ s^{-1}$. The initial concentration of $N_2O_5$ is $0.25 \ mol \ L^{-1}$. How much time is required to produce $0.20 \ mol \ L^{-1}$ concentration of $NO_2$ (in $s$)?