Question

Assertion :Larger is the activation energy, lesser is the effect of a given temperature rise on rate constant 'K'. Reason: $K=A{e}^{-E_a/RT}$.

• A. Both Assertion and Reason are correct and Reason is the correct explanation for Assertion
• B. Both Assertion and Reason are correct but Reason is not the correct explanation for Assertion
• C. Assertion is correct but Reason is incorrect
• D. Assertion is incorrect but Reason is correct

Answer 1

The correct option is D Assertion is incorrect but Reason is correct

Option (D) is correct.
$\left(A\right)$ : Higher activation energy, greater is the effect of given temperature rise on rate constant '$K$'.
Activation energy is the minimum energy needed for the reaction to occur. When temperature increases, $KE$ also increases; as temperature increases, more molecules have higher $KE$, and thus the fraction of molecules that have high enough $KE$ to overcome the energy barrier also increases.
The fraction of molecules with energy equal to or greater than $E_a$ is given by :
$K=A{e}^{-E_a/RT}$.