Rate of a reaction can be expressed by Arrhenius equation as: \(\mathrm{k}=\mathrm{A} \mathrm{e}^{-\mathrm{E} / \mathrm{RT}}\) In this equation, E represents

(A) the energy above which all the colliding molecules will react

(C) the total energy of the reacting molecules at a temperature, T

(D) the fraction of molecules with energy greater than the activation energy of the reaction

JEE Main · 2006 · 30 Apr 2006 · Offline · Chemical Kinetics

Rate of a reaction can be expressed by Arrhenius equation as:

k = A e^{- E / RT}

In this equation, E represents

(A)the energy above which all the colliding molecules will react
(B)the energy below which colliding molecules will not react✓ Correct
(C)the total energy of the reacting molecules at a temperature, T
(D)the fraction of molecules with energy greater than the activation energy of the reaction

Answer: (B)

Solution

In the Arrhenius expression

k = A e^{- E / R T}

the quantity

E

is the activation energy, the threshold a collision must clear before reaction can occur. Molecules colliding with less than this energy cannot surmount the barrier and simply separate unchanged, while those with energy at or above it may react, the exponential term giving the fraction that qualify. Hence

E

represents the energy below which colliding molecules will not react.

JEE Main · 2006 · 30 Apr 2006 · Offline · Single correct option

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JEE Main · 2006 · 30 Apr 2006 · Offline · Chemical Kinetics

Solution

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