Consider two mechanisms below: 2I- (aq) + S2O8 2- (aq) → I2 (aq) + 2SO22-(aq) (a

Consider two mechanisms below: 2I- (aq) + S2O8 2- (aq) → I2 (aq) + 2SO22-(aq) (a) Rate law for (a) is Rate = k[I-] [S2O82-] and similar with the experiment’s rate law.2I- (aq) + S2O8 2- (aq) → I+ (aq) + 2SO42- (aq)  (b) slowI-              + I+ (aq) → I2 (aq)      fastOverall reaction: 2I- (aq) + S2O8 2- (aq) → I2 (aq) + 2SO42- (aq)And Rate = k[I-]2 Activation energy of the experiment is 72.59 kJ/mol which means the reaction is exothermic. which mechanism should be the best fitted mechanism? why?