The reaction between hydroxide ions and bromomethane is first order with respect to $\left[{\mathrm{OH}}^{-}\right]$ and first order with respect to $\left[{\mathrm{CH}}_3\mathrm{Br}\right]$.
${\mathrm{CH}}_3\mathrm{Br}+{\mathrm{OH}}^{-}\to {\mathrm{CH}}_3\mathrm{OH}+{\mathrm{Br}}^{-}$
Suggest a practical method that would confirm that the reaction is first order with respect to $\left[{\mathrm{OH}}^{-}\right]$
- Your method should include details of measurements that would be taken in order to calculate the rate of the reaction.
- You should include a method of presenting the results to show that the reaction is first order with respect to $\left[{\mathrm{OH}}^{-}\right]$.

To confirm the order of reaction with respect to the concentration of hydroxyl ions,
first, we need to run the experiment at a constant temperature and with an excess concentration of bromomethane so that change in concentration of bromomethane does not affect the Rate of Reaction.
The time interval must be fixed and the reaction must be run at different initial concentrations of hydroxyl ion.
To calculate the hydroxyl concentration, titrate the solution with the know solution of acid.
finally processing of results – plot graph of $[\mathrm{O}{\mathrm{H}}^{–}]$ vs time and look for constant half-life.
A similar experiment can be done for the measurement of the order of reaction with respect to the concentration of bromomethane in the presence of an excess hydroxyl concentration and at a fixed temperature. The concentration of remaining bromomethane can be determined with the help of a silver solution.