Exergonic reaction

Exergonic reaction

An exergonic reaction is a chemical reaction that involves a net release of free energy is a chemical reaction where the variation of Gibbs free energy is negative [IUPAC Gold Book definition [http://www.iupac.org/goldbook/E02262.pdf#search='Exergonic%20reaction' Link] ] . This tells us the direction that the reaction will follow. At constant temperature, constant pressure an exergonic reaction is signified by condition:

:Delta G^circ < 0

which describes a chemical reaction that releases energy in the form of heat, light, etc. Exergonic reactions are a form of exergonic processes in general or spontaneous processes and the opposite is called an endergonic reaction. Exergonic reactions are said to occur "spontaneously" but this does not imply that the reaction will take place unconstrained. For instance the reaction between hydrogen and oxygen is very slow and not observed in absence of a suitable catalyst. It has been suggested to replace the term "spontaneous" with "eager" ["Use of the world "eager" instead of "spontaneous" for the description of exergonic reactions" Hamori, Eugene; Muldrey, James E. Journal of Chemical Education 1984, 61, 710] .

Key points

* The concepts exothermic and its opposite number endothermic relate to the enthalpy change in any process not just a chemical reaction.
* the conceptually related endotherm and exotherm are concepts in Animal physiology.

References

External links

* Exergonic vs Endergonic reactions [http://www.d.umn.edu/biology/courses/bio1011/exergonictable.htm Link]


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