How can I calculate the activation energy of a reaction?
You can calculate the activation energy of a reaction by measuring the rate constant k over a range of temperatures and then use the Arrhenius Equation to find
According to his theory molecules must acquire a certain critical energy
From BBC GCSE:
A is a constant termed the frequency factor
e is the base of natural logs
R is the gas constant = 8.31J/K/mol
T is the absolute temperature in degrees Kelvin.
If you take natural logs of both sides of the equation you get:
You then measure k over a range of temperatures, the method you use depends very much on the type of reaction you are studying.
You can then plot
So the gradient of the line is equal to
This is an example taken from Wikipedia relating to the decomposition of nitrogen (IV) oxide.