Chemistry - Chemical Kinetics Question with Solution | TestHub

The rate of a complex reaction is determined by the slowest step in its mechanism, known as the rate-determining step.

The given slow step is:
${\mathrm{NO}}_2{\mathrm{Cl}}_{(\mathrm{g})}⟶{\mathrm{NO}}_{2(\mathrm{g})}+{\mathrm{Cl}}_{(\mathrm{g})}$

The rate law equation is written based on the concentration of the reactants in the slow step.

Therefore, the rate law equation is:
$\mathrm{r}=\mathrm{k}[{\mathrm{NO}}_2\mathrm{Cl}]$

Answer: $\mathrm{r}=\mathrm{k}\left[{\mathrm{NO}}_2\mathrm{Cl}\right]$