Chemistry
Thermodynamics of Surface Adsorption: Langmuir and Freundlich Isotherms
Quick fact
The Langmuir isotherm, derived from kinetic and thermodynamic arguments, assumes a perfectly uniform surface with one molecule per site, yet it fails for many real solids where adsorption sites are not equal—a fact that spurred the empirical Freundlich model, which embraces surface heterogeneity and gives a realistic fit for multilayer adsorption.
Why this is interesting
Ever wonder how activated carbon strips toxins from water or how catalysts grab onto reactants? It all comes down to molecules sticking to surfaces—a dance between energy and disorder that follows surprisingly simple rules.