Rate Law Calculator
Apply the Arrhenius equation to rates.
About Rate Law Calculator
The Arrhenius equation for Rate Law scales a pre-exponential factor by the exponential of the negative activation energy over the gas constant and temperature. Even a small rise in temperature raises the rate constant sharply because it sits inside an exponential.
Formula
Rate Law
k = A.exp(-Ea/RT)
- A
- How often collisions have the right geometry
- Ea
- Energy barrier reactants must clear
Worked example
With the default values below, Rate Law Calculator returns Rate Constant of 2,954,161.125. Change any input above and every figure here is recalculated in your browser.
Inputs used
- Pre-exponential factorminimum 0
- 10,000,000,000,000
- Activation energyminimum 0 J/mol
- 50,000 J/mol
- Temperatureminimum 0 K
- 400 K
Results
- Rate Constant
- 2,954,161.125
- log10(k)
- 6.470
- Boltzmann Factor
- 0.00000030
Step by step
- 1Values used
- 2Rate Law
- 3Rate Constant= 2,954,161.125
- 4log10(k)= 6.470
- 5Boltzmann Factor= 0.00000030
Assumptions and limits
- The result is derived only from the 3 inputs listed above. Anything not among them is not part of the calculation.
- In particular, this calculator does not take inflation, fees or charges or compounding frequency into account.
- Figures are rounded for display to 8 decimal places, so totals built from several rounded parts can differ slightly from the unrounded arithmetic.
How these calculators are built and tested is described on the Methodology page. If a figure looks wrong, please report it.
Frequently Asked Questions
How is Rate Law calculated?
k = A.exp(-Ea/RT) The Arrhenius equation for Rate Law scales a pre-exponential factor by the exponential of the negative activation energy over the gas constant and temperature.
Why does Rate Law matter?
Even a small rise in temperature raises the rate constant sharply because it sits inside an exponential.
What values do I need to enter?
This calculator takes 3 inputs: Pre-exponential factor, Activation energy, Temperature. The pre-filled defaults are a realistic starting point — replace them with figures from your own environment for a result you can act on.