Enter the temperature, rate coefficient, and constant. The activation energy calculator will evaluate and display the total activation energy.

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## Activation Energy Formula

The following equation can be used to calculate the activation energy of a reaction.

E = -R * T * ln(k/A)

- Where E is the activation energy
- R is the gas constant
- T is the temperature
- k is the rate coefficient
- A is the constant

To calculate the activation energy, multiply the gas constant by the temperature, then multiply by the natural log of the ratio of the rate coefficient over the constant.

## Activation Energy Definition

Activation Energy is the total energy needed for a chemical reaction to occur. It’s most often used in chemistry and thermodynamics. These reactions can include things like combustion.

## Activation Energy Example

How to calculate an activation energy?

**First, determine the temperature.**Measure the temperature of the substance.

**Next, determine the rate coefficient.**Measure or calculate the rate coefficient.

**Next, determine the constant A.**Empirically determine the constant A.

**Finally, calculate the activation energy.**Using the formula above, calculate the activation energy.

## FAQ

**What is an activation energy?**

Activation energy is the total energy required for a chemical reaction to occur.