Arrhenius equation

noun

Ar·​rhe·​ni·​us equation ə-ˈrē-nē-əs- 

-ˈrā-

variants or less commonly Arrhenius relation

chemistry

: an equation describing the mathematical relationship between temperature and the rate of a chemical reaction

Note: The Arrhenius equation is sometimes expressed as k = Ae^-E/RT where k is the rate of chemical reaction, A is a constant depending on the chemicals involved, E is the activation energy, R is the universal gas constant, and T is the temperature.

What we're really looking at here is what's known as the Arrhenius equation. Svante August Arrhenius was a Nobel Prize winning Swedish chemist around the turn of the century. He observed that an increase of 18° F will about double the rate of the average chemical reaction. And the same holds true in reverse: the colder the temperature, the less the rate of reaction.

—Matt Kramer, Wine Spectator, 15 May 1998

Ideas from elementary statistical mechanics allowed determination of the energies displayed in the figure: The activation barriers were obtained using the Arrhenius relation, whereas the Boltzmann relation was used to determine the bound-state energy difference.

—Harold J. W. Zandvliet et al., Physics Today, July 2001

Word History

Etymology

after Svante August Arrhenius †1927 Swedish chemist

First Known Use

1902, in the meaning defined above

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