We’re being asked to **determine the activation energy (E _{a})** 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 **k _{1}** = rate constant at T

**k _{2}** = rate constant at T

**E _{a}** = activation energy (in J/mol)

**R** = gas constant (8.314 J/mol•K)

**T _{1} and T_{2}** = temperature (in K)

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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