The ratio of the time taken to complete $60\%$ and $20\%$ of a first-order reaction $[A \rightarrow \text{product}]$ is : $(\log 2 = 0.3)$

$A$ flask contains a mixture of compounds $A$ and $B.$ Both compounds decompose by first-order kinetics. The half-lives for $A$ and $B$ are $300 \ s$ and $180 \ s,$ respectively. If the concentrations of $A$ and $B$ are equal initially,the time required for the concentration of $A$ to be four times that of $B$ (in $s$): (Use $\ln 2 = 0.693$)

If $50\%$ of a reaction occurs in $100 \ s$ and $75\%$ of the reaction occurs in $200 \ s$,the order of this reaction is

For a reaction,the rate constant is $2.34 \ s^{-1}$. The half-life period for the reaction is ....... $s.$

The unit of the specific reaction rate constant for a first-order reaction (if the concentration is expressed in molarity) is:

The time required for a first-order reaction to be $90\%$ complete is approximately .........