1. What is Activation Energy?

Activation energy (Ea) is the minimum amount of energy required for a chemical reaction to occur. It represents the energy barrier that must be overcome for reactants to transform into products.

2. How Does the Calculator Work?

The calculator uses the Arrhenius equation:

Where:

• \( Ea \) — Activation energy (J/mol)
• \( R \) — Universal gas constant (8.314 J/mol·K)
• \( k1, k2 \) — Rate constants at temperatures T1 and T2
• \( T1, T2 \) — Absolute temperatures in Kelvin

Explanation: The equation relates the rate constants of a reaction at two different temperatures to the activation energy.

3. Importance of Activation Energy

Details: Activation energy determines how sensitive a reaction is to temperature changes. Lower activation energy means the reaction proceeds more easily.

4. Using the Calculator

Tips: Enter rate constants (k1, k2) and their corresponding absolute temperatures in Kelvin (T1, T2). All values must be positive and T1 ≠ T2.

5. Frequently Asked Questions (FAQ)

Q1: What are typical activation energy values?
A: Most chemical reactions have Ea between 50-250 kJ/mol. Biological reactions often have lower values (10-100 kJ/mol).

Q2: How does catalyst affect activation energy?
A: Catalysts lower the activation energy by providing an alternative reaction pathway, increasing reaction rate.

Q3: Why use natural logarithm in the equation?
A: The natural logarithm (ln) comes from the exponential relationship in the Arrhenius equation between rate constant and temperature.

Q4: What are the limitations of this calculation?
A: Assumes the reaction follows Arrhenius behavior over the temperature range and that the mechanism doesn't change.

Q5: Can I use Celsius temperatures?
A: No, you must convert to Kelvin (K = °C + 273.15) as the equation requires absolute temperature.