Enter the forward activation energy (J) and the change in enthalpy (J/mol) into the calculator to determine the Reverse Activation Energy. 

Reverse Activation Energy Formula

The following equation is used to calculate the Reverse Activation Energy. 

RAE = FAE – dH


  • Where RAE is the Reverse Activity Energy (J)
  • FAE is the forward activation energy (J) 
  • dH is the change in enthalpy (J/mol) 

How to Calculate Reverse Activity Energy?

The following two example problems outline the steps and information needed in order to calculate the Reverse Activity Energy.

Example Problem #1:

  1. First, determine the forward activation energy (J). In this example, the forward activation energy (J) is measured to be 41.
  2. Next, determine the change in enthalpy (J/mol). For this problem, the change in enthalpy (J/mol) is calculated to be 3.
  3. Finally, calculate the Reverse Activation Energy using the formula above: 

RAE = FAE – dH

Inserting the values from above and solving the equation with the imputed values gives: 

RAE = 41 – 3= 38(J)

Example Problem #2: 

Using the same process as example problem 1, we first define the needed variables outlined by the formula. In this case, the values are provide as: 

forward activation energy (J) = 400

change in enthalpy (J/mol) = 24

Entering these values into the formula or calculator above gives us: RAE = 400 – 24 = 376 (J)