Calculate the rate constant of the first order reaction if $20 \%$ of the reactant decomposes in $15 \ minutes$.

For the given first order reaction $A \rightarrow B$,the half-life of the reaction is $0.3010 \ min$. The ratio of the initial concentration of reactant to the concentration of reactant at time $2.0 \ min$ will be equal to $........$ (Nearest integer).

The reaction $2N_2O_5 \,(g) \to 4NO_2 \,(g) + O_2 \,(g)$ follows first order kinetics. The pressure of a vessel containing only $N_2O_5$ was found to increase from $50 \, mmHg$ to $87.5 \, mmHg$ in $30 \, min$. The pressure exerted by the gases after $60 \, min$ will be .......... $mmHg$ (assume temperature remains constant).

In a first order reaction,the concentration of the reactant is reduced from $0.6 \ mol \ L^{-1}$ to $0.2 \ mol \ L^{-1}$ in $5 \ min$. What is the rate constant of the reaction (in $min^{-1}$)? $(\log 3 = 0.4771)$

$A$ first-order reaction takes $69.3 \ min$ to complete $50\%$ of the reaction. How much time (in $min$) will it take to complete $80\%$ of the reaction?

Which one of the following plots is correct for a first order reaction?