Activation Energy Calculator

Calculate activation energy using the Arrhenius equation.
Calculator
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Results
Activation Energy (Ea)
40.20 kJ/mol
In Joules
40201.75 J/mol
Reaction Kinetics Analysis
Energy barriers and temperature sensitivity

Energy Barrier

Activation Energy (Ea):40.20 kJ/mol
Rate Change:10.00x

Reaction Interpretation

Low activation energy. The reaction proceeds relatively fast even at lower temperatures.

Arrhenius Insight

According to the Arrhenius equation, a 10 C increase in temperature typically doubles the reaction rate for reactions with moderate activation energies (~50 kJ/mol). Your data shows a 10.0x increase over a 50K difference.

How to Use

Step-by-step instructions
  1. 1Enter rate constant k1 and temperature T1 (in Kelvin).
  2. 2Enter rate constant k2 and temperature T2 (in Kelvin).
  3. 3The calculator will compute the Activation Energy (Ea).

Arrhenius Equation

Relates the rate constants (k) at two different temperatures (T) to the activation energy (Ea).
ln(k2/k1) = (-Ea/R)(1/T2 - 1/T1)

Variables:

kRate constant
TTemperature (Kelvin)
RGas constant (8.314 J/mol*K)

Example

Reaction Rates

Inputs:

k1:1.0 at 300K
k2:10.0 at 350K

Steps:

  1. 1.ln(10/1) = 2.302
  2. 2.1/350 - 1/300 = -0.000476
  3. 3.Ea = -8.314 x 2.302 / -0.000476 = 40,200 J/mol
Result:
40.2 kJ/mol

Frequently Asked Questions

Must temperature be in Kelvin?

Yes, thermodynamic calculations require absolute temperature (Kelvin).