Activation Energy for First Order Reaction Calculator

Activation Energy Formula:

\[ E_a = [R] \times T \times \ln\left(\frac{A}{k}\right) \]

Activation Energy (J/mol):

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1. What is Activation Energy for First Order Reaction?

Definition: Activation energy is the minimum amount of energy required to initiate a chemical reaction.

Purpose: This calculator determines the activation energy for first-order reactions using the Arrhenius equation.

2. How Does the Calculator Work?

The calculator uses the formula:

\[ E_a = [R] \times T \times \ln\left(\frac{A}{k}\right) \]

Where:

\( E_a \) — Activation energy (J/mol)
\( [R] \) — Universal gas constant (8.314 J/mol·K)
\( T \) — Absolute temperature (K)
\( A \) — Frequency factor (m³/mol·s)
\( k \) — Rate constant (1/s)

Explanation: The formula is derived from the Arrhenius equation and calculates the energy barrier that must be overcome for the reaction to occur.

3. Importance of Activation Energy

Details: Activation energy determines the reaction rate and temperature dependence. Lower activation energy means faster reaction rates.

4. Using the Calculator

Tips: Enter the temperature in Kelvin, frequency factor in m³/mol·s, and rate constant in 1/s. All values must be > 0.

5. Frequently Asked Questions (FAQ)

Q1: What is the frequency factor (A)?
A: It represents the frequency of molecular collisions with proper orientation for reaction.

Q2: How does temperature affect activation energy?
A: Higher temperatures provide more energy to overcome the activation barrier, increasing reaction rates.

Q3: What are typical activation energy values?
A: Most reactions have Ea between 50-250 kJ/mol, though some can be lower or higher.

Q4: Can this calculator be used for non-first-order reactions?
A: No, this specific formula applies only to first-order reactions.

Q5: Why use natural logarithm in the formula?
A: The natural log (ln) comes from the mathematical derivation of the Arrhenius equation.