In chemical kinetics a reaction rate constant k or quantifies the speed of a chemical reaction.
For a chemical reaction where substance A and B are reacting to produce C, the reaction rate has the form:
- Reaction: A + B → C
k(T) is the reaction rate constant that depends on temperature.
is the concentration of substance A in moles per volume of solution assuming the reaction is taking place throughout the volume of the solution (for a reaction taking place at a boundary it would denote something like moles of A per area).
The exponents m and n are called partial orders and depend on the reaction mechanism. They can be determined experimentally.
A single-step reaction can also be written as
Ea is the activation energy and R is the gas constant. Since at temperature T the molecules have energies according to a Boltzmann distribution, one can expect the proportion of collisions with energy greater than Ea to vary with e-Ea/RT. A is the pre-exponential factor or frequency factor.
The Arrhenius equation gives the quantitative basis of the relationship between the activation energy and the reaction rate at which a reaction proceeds.
Read more about Reaction Rate Constant: Units, Plasma and Gases
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