The half-life period of a $1^{st}$ order reaction is $60 \ minutes$. What percentage will be left over after $240 \ minutes$ (in $\%$)?

The decomposition of $N_2O_5$ occurs as $2N_2O_5 \to 4NO_2 + O_2$ and follows first-order kinetics. Hence,

For the first-order isomerization reaction $A \rightarrow B$,the rate constant is $4.5 \times 10^{-3} \ min^{-1}$. If the initial concentration of $A$ is $1 \ M$,find the rate of the reaction after $1 \ hour$.

If the concentration is expressed in $mol \ L^{-1}$,the unit of the rate constant for a first-order reaction is........

For a first order reaction,the ratio of the time for $75 \% $ completion of a reaction to the time for $50 \% $ completion is $....$ . (Integer answer)

For a reaction $A \rightarrow$ product,the rate constant is $2 \times 10^{-2} \ s^{-1}$. The initial concentration of $A$ is $1.0 \ mol \ dm^{-3}$. What is the value of $\log \frac{1}{[A]_{t}}$ after $100 \ s$?