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at a particular temperature and fitting the data to the
Arrhenius equation. The pre-exponential factor is generally not exactly constant, but rather depends on the specific reaction being studied and the temperature at which the reaction is occurring.
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The units of the pre-exponential factor A are identical to those of the rate constant and will vary depending on the order of the reaction. For a first-order reaction, it has units of s. For that reason, it is often called
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316:"How do you calculate the pre-exponential factor from the Arrhenius equation?"
262:{\displaystyle A={\frac {k}{e^{-{\frac {E_{a}}{RT}}}}}=ke^{\frac {E_{a}}{RT}}}
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Numerical constant in the
Arrhenius equation in Chemical Kinetics
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IUPAC Gold Book definition of pre-exponential factor
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139:is the pre-exponential constant in the
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