Kinetics:  Rate

Chemical Kinetics - The study of the rates of chemical reactions.
Rate of a Reaction - The change in concentration of one of the reactants (DX), during a given period of time (Dt)

The reaction rate gradually decreases as reactants are consumed.
Instantaneous Rate of Reaction - The rate of a reaction at an instant in time.
where d(X)/dt is the derivative X/t in terms of t.
Rate Law - An equation that describes how the rate of a chemical reaction depends on the concentrations of the reactants consumed in that reaction.
rate = k[O3]
Rate Constant (k) - The proportionality constant in the rate law equation that describes the relationship between  the rate of a step in a chemical reaction and the product of the concentrations of the reactants consumed in that step.
**The rate law for a reaction cannot be determined by the coefficients of the balanced reaction; it must be determined experimentally.
For gas equilibrium equations, the equilibrium constant (Kc) is equal to the rate constant for the forward reaction divided by the rate constant of the reverse reaction.
See Sample Rate Calculations
For the reaction:
where a, b, c, d are the coefficients for the reactants and products A, B, C, D
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