Which factor in Arrhenius equation, corresponds to fraction of molecules having kinetic energy greater than activation energy?

$e^{-Ea/RT}$

The correct answer is Option (4) → $e^{-Ea/RT}$.

In the Arrhenius equation, the term that corresponds to the fraction of molecules having kinetic energy greater than the activation energy (\(E_a\)) is:

\(e^{-\frac{E_a}{RT}}\)

The Arrhenius equation is given by:

\(k = A e^{-\frac{E_a}{RT}}\)

where:

\(k\) = rate constant of the reaction

\(A\) = pre-exponential factor (frequency factor)

\(E_a\) = activation energy

\(R\) = universal gas constant

\(T\) = absolute temperature (in Kelvin)

Breakdown of the Terms

\(e^{-\frac{E_a}{RT}}\):

This term represents the fraction of molecules that have enough kinetic energy to overcome the activation energy barrier for the reaction to occur. The higher the temperature \(T\) or the lower the activation energy \(E_a\), the larger this fraction becomes, leading to an increase in the rate constant \(k\).

\(lnk\) and \(lnA\):

These terms are logarithmic forms related to the rate constant \(k\) and the pre-exponential factor \(A\) respectively, but they do not directly represent the fraction of molecules.

\(RT\):

This term is part of the equation used to relate temperature to the energy available to molecules, but it does not directly correspond to the fraction of molecules having sufficient energy.

Thus, the correct answer is: \(e^{-\frac{E_a}{RT}}\)