The rate for reaction $$2 \mathrm{~A}+\mathrm{B} \rightarrow$$ product is $$6 \times 10^{-4} \mathrm{~mol} \mathrm{~dm}^{-3} \mathrm{~s}^{-1}$$ Calculate the rate constant if the reaction is first order in $$\mathrm{A}$$ and zeroth order in $$\mathrm{B}$$. [Given $$[\mathrm{A}]=[\mathrm{B}]=0.3 \mathrm{M}]$$

Calculate half life of first order reaction if rate constant of reaction is $$2.772 \times 10^{-3} \mathrm{~s}^{-1}$$

Which from following statements about rate constant is NOT true?

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?