Question

Which one of the following does not represent Arrhenius equation?

• A. \(\log k=\log A-\frac{Ea}{2.303RT}\)
• B. \(k=Ae^{-Ea/RT}\)
• C. \(In\;k=-\frac{Ea}{RT}+In\;A\)
• D. \(k=Ae^{Ea/RT}\)

Answer 1

The Correct Option is D

The Arrhenius equation describes how the rate constant \( k \) depends on the temperature \( T \) and activation energy \( E_a \). The correct form of the Arrhenius equation is:

\[ k = Ae^{-\frac{E_a}{RT}} \]

Where:

• \( k \) is the rate constant.
• \( A \) is the pre-exponential factor (frequency factor).
• \( E_a \) is the activation energy.
• \( R \) is the gas constant.
• \( T \) is the temperature in Kelvin.

Which of the following does not represent the Arrhenius equation?

• (A) \( \log k = \log A - \frac{E_a}{2.303RT} \) is a valid transformation of the Arrhenius equation.
• (B) \( k = Ae^{-E_a/RT} \) is the correct form of the Arrhenius equation.
• (C) \( \ln k = -\frac{E_a}{RT} + \ln A \) is also a valid transformation of the Arrhenius equation.
• (D) \( k = Ae^{E_a/RT} \) is incorrect because the exponent should have a negative sign.

The correct answer is (D) because \( k = Ae^{E_a/RT} \) does not represent the correct form of the Arrhenius equation.

Answer 2

The correct form of the Arrhenius equation is: \[ k = A e^{-\frac{E_a}{RT}} \] Where:
\( k \) is the rate constant,
\( A \) is the pre-exponential factor,
\( E_a \) is the activation energy,
\( R \) is the gas constant,
\( T \) is the temperature.

Option (D) shows an incorrect form where \( E_a \) is positive, which does not match the correct Arrhenius equation.