For the reaction,

$$\mathrm{CH}_3 \mathrm{Br}(a q)+\mathrm{OH}^{-}(a q) \longrightarrow \mathrm{CH}_3 \mathrm{OH}(a q)+\mathrm{Br}^{-}(a q),$$

The rate law is rate $$=k\left[\mathrm{CH}_3 \mathrm{Br}\right]\left[\mathrm{OH}^{-}\right]$$. What is change in rate of reaction if concentration of both reactants is doubled?

For the reaction, $$2 A+2 B \longrightarrow 2 C+D$$, the rate law is expressed as rate $$=k[A]^2[B]$$. Calculate the rate constant if rate of reaction is $$0.24 \mathrm{~mol} \mathrm{~dm}^{-3} \mathrm{~s}^{-1}$$.

[[$$A$$]$$=0.5 \mathrm{M}$$ and $$[B]=0.2 \mathrm{M}$$]

Find the rate of formation of $$\mathrm{NO}_{2(\mathrm{~g})}$$ in the following reaction.

$$\begin{aligned} & 2 \mathrm{~N}_2 \mathrm{O}_{5(\mathrm{~g})} \rightarrow 4 \mathrm{NO}_{2(\mathrm{~g})}+\mathrm{O}_{2(\mathrm{~g})} \\ & {\left[\frac{-\mathrm{d}\left[\mathrm{N}_2 \mathrm{O}_5\right]}{\mathrm{dt}}=0.02 \mathrm{~mol} \mathrm{~dm}^{-3}\right]} \end{aligned}$$

Calculate the rate constant of the first order reaction if $$20 \%$$ of the reactant decomposes in 15 minutes.