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What is a frequency factor or pre-expone...

What is a frequency factor or pre-exponential factor?

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In Arrhenius equation, `k=Axx e^(-Ea//RT)` the factor A is called frequency factor and since it is a coefficient of exponential expression, `e^(-E_(a)//RT)` it is also called pre-exponential factor.
In the above equation k is a rate constant at temperature T, `E_(a)` is the energy of activation and R is a gas constant.
A is related to frequency of collisions (Z) or rate of collisions. It is represented as, `A=PxxZ` where P is the probability of collisions with proper orientations and Z is the frequency of collisions of reacting molecules .
The units of A are same as that of k.
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