Bromomethane can undergo a substitution reaction as follows:
CH3Br(l) + OH-(aq) → CH3OH(aq) + Br-(aq)
The rate equation is found to be:
Rate = k[CH3Br][OH-]
The rate constant, k = 3.0 x 10^-4 mol^-1 dm^3 s^-1 at 300K.
a) What is the overall order of reaction?
When a large excess of OH- is used, the reaction is found to be pseudo first order.
b) What does "pseudo first order" mean?
c) What would the apparent reaction order be if excess bromomethane was used instead of excess OH-?
An experiment was done, with the initial concentrations of reactants as follows:
[OH-] = 1.0 x 10^-2 mol dm^-3 and [CH3Br] = 1.0 x 10^-4 mol dm^-3
d) Calculate:
i) The initial rate of reaction
ii) The pseudo first order rate constant