The half-life period for a first-order reaction is . . . . . . .

The half-life of a first order reaction $X \to Y$ is $100 \ min$. The concentration of $X$ would be reduced to $10 \%$ of the initial concentration in .......... $min$.

If the decomposition reaction $A_{(g)} \to B_{(g)}$ follows first-order kinetics,then the graph of the rate of formation $(R)$ of $B$ against time $t$ will be:

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 $t$)

Calculate the half-life of the first-order reaction $C_2H_4O_{(g)} \to CH_{4(g)} + CO_{(g)}$ if the initial pressure of $C_2H_4O_{(g)}$ is $80 \ mm$ and the total pressure at the end of $20 \ minutes$ is $120 \ mm$. (in $min$)

$A$ first order reaction is half completed in $45 \ min$. How long does it need $99.9 \%$ of the reaction to be completed (in $Hours$)?