The reaction between 1-bromopropane (C3H7Br) and thiosulfate ion (S2O32−) in solution under certain conditions at 310K has the following time-independent stoichiometry:
C3H7Br(aq) + S2O32−(aq) = C3H7S2O3−(aq) + Br−(aq)
Reaction 1 was followed by monitoring the decrease in the concentration of 1-bromopropane with time throughout the course of the reaction. From this data the rate of reaction J was obtained by drawing tangents to the kinetic reaction profile at several concentrations of 1-bromopropane. The initial concentrations of 1-bromopropane and thiosulfate are 0.041 and 0.85 mol dm−3 respectively.
Express the rate of reaction J in terms of the rate of change of concentration of thiosulfate ion and bromide ion in Reaction 1.
Suggest a plausible rate equation for Reaction 1.
Explain why the experimental information given in the question above allows you to simplify your rate equation suggested in part (b). Give the simplified or pseudo-order rate equation.