How this calculator works
Choose a per-mole activation energy with the gas constant or a per-molecule energy with the Boltzmann constant. Exponential forms use A, k and absolute temperature. Logarithmic forms use natural logarithms and reciprocal kelvins; their straight-line slope is -Ea/R or -E/kB. The plot assumes constant A and activation energy across your range. Values too large or small to represent as positive finite A and k are rejected.
Formula
k = A exp(-Ea/RT) = A exp(-E/kBT). ln(k) = ln(A) - (Ea/R)(1/T). R = NA kB; kB = 1.380649 x 10^-23 J/K.
Worked example
At 300 K with A = e and Ea = 2494.338785 J/mol, k = 1. If Ea = 0 and A = 10, k stays 10 at every positive temperature and the Arrhenius plot is horizontal.
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Frequently asked questions
What units does k use?
Use the rate-constant units appropriate to the reaction order; A must use the same units.
Are log and ln interchangeable?
This page uses natural logarithms. Base-10 logarithms would require a factor ln(10).
Why limit the plot size?
Up to 500 points fit the chart engine. Increase the temperature step for a wider range.