i have a problem: The reaction, H3AsO3 + I3- + H2O = H3AsO4 + 3I- + 2H+ has the following mechanism where the 3rd step is : H3AsO3 H2AsO3- + H+ (Equilibrium constant K1) I3- + H2O 2I- + H2OI+ (Equilibrium constant K2) H2OI+ + H2AsO3- H2AsO3I + H2O (rds., k1) H2AsO3I I- + H2AsO3+ (Equilibrium constant K3) H2AsO3+ + H2O H3AsO4 + H+ (Equilibrium constant K4)

Ki = Kioexp{-H/RT}; k1 = k1o exp{-E/RT}

a. Derive a rate expression that contains concentrations of only the stable reactants and products.

b. What do you expect for the observed activation energy for this reaction?