Arrhenius Equation Calculator
Rate constants, and where the 'doubles per 10 degrees' rule comes from.
Work out Arrhenius Equation. Rate constants, and where the 'doubles per 10 degrees' rule comes from. Free, with no account and nothing to download.
Rate constant k
17,393.1797
1.924× faster per 10 K
k = A·e^(−Ea/RT). The exponential is why the old laboratory rule of thumb — that reaction rate roughly doubles for every 10 °C — holds at all: it is not a law, it is what this equation produces for activation energies around 50 kJ/mol near room temperature. Change Ea and the factor changes with it, which the row above makes visible.
How the Arrhenius Equation Calculator works
k = A·e^(−Ea/RT). The old laboratory rule that reaction rate roughly doubles every 10 °C is not a law — it is what this equation produces for activation energies around 50 kJ/mol near room temperature. Change Ea and the factor changes with it.
Also known as: activation energy calculator · rate constant calculator · arrhenius formula · how to calculate activation energy
Frequently asked questions
What is the Arrhenius equation?
k = A·e^(−Ea/RT), relating the rate constant to activation energy and absolute temperature.
Does reaction rate really double every 10 degrees?
Only approximately, and only for typical activation energies near room temperature. This page shows the actual factor for your figures rather than repeating the rule of thumb.
What is the pre-exponential factor?
Roughly, how often correctly-oriented collisions occur. It sets the ceiling the exponential term scales down from.
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