In general, chemical reactions are possible if the reaction products have lower energy than the reactants. But the reaction only proceeds if sufficient energy is available to exceed the activation energy (ΔH1) for the reaction. Many catalysts work by providing a reaction pathway which has a lower activation energy (ΔH2) than the uncatalyzed reaction. The overall heat of reaction (ΔH) remains the same.
Related category PHYSICAL CHEMISTRY
Home • About • Copyright © The Worlds of David Darling • Encyclopedia of Alternative Energy • Contact