Ch ical chemistr Reaction Kinetic Reaction mechanisms Reaction actually occurs 2SO2+O2-A,2O3 02+2AO→O (177) intermediate (O2)+SO2→MO+SO3 2N2O5>4MO2+O2 Elementary reaction Step(a) N2O令→NO2+MO3 Step(b NO2+NO3→NO+O2+NO2 (178) Step(c) NO+NO3→>2NO29 Physical Chemistry Reaction Mechanisms NO2 + SO2 → NO+ SO3 O2 + 2NO →2NO2 (17.7) 2SO2 O2 2SO3 NO + ⎯ ⎯→ intermediate 2N2 O5 → 4NO2 +O2 N2 O5  NO2 + NO3 NO+ NO3 → 2NO2 NO2 + NO3 → NO+O2 + NO2 (17.8) Step (a) Step (b) Step (c) Elementary reaction Reaction actually occurs Reaction Kinetics