A certain reaction has a rate constant of 8.8 s^-¹ at 298 K and 140 s^-¹ at 323 K .What is the activation energy for this reaction? A) 38 kJ.mol^-¹ B) 89 kJ.mol^-¹ C) 120 kJ.mol^-¹ D) 23 kJ.mol^-¹ E) 1.2 kJ.mol^-¹

Question

Quizplus · Accepted Answer

The activation energy can be calculated using the Arrhenius equation: 
k = A * exp(-Ea/RT)
Taking the natural logarithm of both sides, we get:
ln k = ln A - (Ea/RT)
We can then use the data provided at two different temperatures to solve for Ea:
ln(140/8.8) = (Ea/R) * ((1/298) - (1/323))
Solving for Ea gives us approximately 89 kJ/mol. Therefore, the best choice is B, with an activation energy of 89 kJ/mol.

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