Problem: A first-order reaction proceeds with a rate constant of 1.5x10  -5 s-1 at 25°C and 2.7x10-3 s-1 at 75°C. According to the Arrhenius equation, what is the activation energy of this reaction in kJ/mol?A. 89.5 kJ/molB. 1.30 kJ/molC. 16.2 kJ/molD. 95.8 kJ/mol

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FREE Expert Solution

We’re being asked to determine the activation energy (Ea) of a reaction. We’re given the rate constants at two different temperatures.


This means we need to use the two-point form of the Arrhenius Equation:



where k1 = rate constant at T1

k2 = rate constant at T2

Ea = activation energy (in J/mol)

R = gas constant (8.314 J/mol•K)

T1 and T2 = temperature (in K)


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Problem Details

A first-order reaction proceeds with a rate constant of 1.5x10  -5 s-1 at 25°C and 2.7x10-3 s-1 at 75°C. According to the Arrhenius equation, what is the activation energy of this reaction in kJ/mol?

A. 89.5 kJ/mol

B. 1.30 kJ/mol

C. 16.2 kJ/mol

D. 95.8 kJ/mol

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