List of top Physical Chemistry Questions on Chemical Kinetics

At 30$^\circ$C, the half-life for the decomposition of a compound is 100 seconds and the value of the half-life is independent of the initial concentration of the reactantThe time required for 30\% of the reactant to be consumed is _ _ _ seconds. (rounded off to one decimal place)

For the reaction NO$_2$Cl $\rightarrow$ NO$_2$ + $\frac{1}{2}$Cl$_2$, the proposed mechanism involves the following two elementary steps:
NO$_2$Cl $\xrightarrow{k_1}$ NO$_2$ + Cl
NO$_2$Cl + Cl $\xrightarrow{k_2}$ NO$_2$ + Cl$_2$
Assuming steady state approximation for Cl, the correct expression for the rate of formation of NO$_2$ is