1 Chapter 12 - Chemical Kinetics 12.1 Reaction Rates A. Chemical kinetics 1. Study of the speed with which reactants are converted to products B. Reaction Rate 1. The change in concentration of a reactant or product per unit of time [ ] t A tt ttimeatAofionconcentratttimeatAofionconcentratRate D D=- -= 12 12 a. Rates decrease with time b. It is customary to express reaction rates as positive values c. Instantaneous rate can be determined by finding the slope of a line tangent to a point representing a particular time C. Decomposition of NO2 2NO2(g) ? 2NO(g) + O2(g) Rate of consumption of NO2 = rate of production of NO = 2(rate of production of O2) [ ]t NO D D- 2 = [ ] t NO D D = [ ] ? ?