Temperature Dependence
Each reaction rate coefficient k has a temperature dependency, which is usually given by the Arrhenius equation:
Ea is the activation energy and R is the gas constant. Since at temperature T the molecules have energies given by a Boltzmann distribution, one can expect the number of collisions with energy greater than Ea to be proportional to . A is the pre-exponential factor or frequency factor.
The values for A and Ea are dependent on the reaction. There are also more complex equations possible, which describe temperature dependence of other rate constants that do not follow this pattern.
A chemical reaction takes place only when the reacting molecules collide. However all collisions are not effective in causing the reaction. Products are formed only when the colliding molecules possess a certain minimum energy called threshold energy. Basically, the number of activated molecules nearly doubles for a temperature T+10 kelvin. The ratio of a reaction at a given temperature to its rate constant at a temperature 10 degree lower is called temperature co-efficient.
Read more about this topic: Reaction Rate
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