Heterogeneous Reaction Definition

Beakers of colored liquids

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A heterogeneous reaction is a chemical reaction where the reactants are in different phases from each other. In a homogeneous reaction, the reactants are in the same phase as one another.


The reaction between acid and metal is a heterogeneous reaction. A reaction between a gas and a liquid, as between air and seawater, is heterogeneous. A reaction at the surface of a catalyst is heterogeneous. In contrast, a reaction between two miscible liquids or between two gases is homogeneous.


  • Guéguen, Yves; Palciauskas, Victor (May 1994). Introduction to the Physics of Rocks. Princeton University Press. ISBN 978-0-691-03452-2.