• At higher temperatures, a greater proportion of molecules have energy greater than than the activation energy
• Since the?rate constant?and?rate of reaction?is?directly proportional?to the fraction of molecules with energy equal or greater than the activation energy, then at higher temperatures:
  • The?rate constant?increases
  • The?rate of reaction?increases
• The relationship between the rate constant and the temperature is given by the following equation:

ln?k?= natural logarithm of the rate constant

A?= constant related to the collision frequency and orientation of the molecules

E_a?= activation energy (joules, J)

R?= gas constant (8.31 J K^-1?mol^-1)

T?= temperature (kelvin, K)

• A?varies only a little bit with temperature, it can be considered a constant
• E_a?and?R?are also constants

• The equation shows that an?increase?in temperature (higher value of?T) gives a?greater?value of ln?k?(and therefore a higher value of?k)
• Since the?rate of the reaction?depends on the?rate constant?(k) an increase in?k?also means an increased rate of reaction

The graph of ln k over 1/T is a straight line with gradient -E_a/R