The velocity constant of a first-order reaction is expressed in the units:

The rate equation for a first-order reaction is given by $[R] = [R]_0 e^{-kt}$. $A$ straight line with a positive slope is obtained by plotting: ($[R]_0 =$ initial concentration of reactant,$[R] =$ concentration of reactant at time $t$)

Which among the following represents the expression for the $\left(\frac{3}{4}\right)^{\text{th}}$ life of a $1^{\text{st}}$ order reaction?

In a first order reaction,the concentration of the reactant is reduced to $25\%$ in one hour. The half-life period of the reaction is: (in $hr$)

For a first order reaction, the half-life is $5 \text{ hour}$. What time is required to reduce $10 \text{ g}$ of reactant to $2.5 \text{ g}$ (in $\text{ hour}$)?

If the rate constant for a first order reaction is $k$,then find the time required for completion of $80 \%$ of the reaction.