Langmuir
Freundlich
BET
— sweep marker follows relative pressure
Surface coverage (focused model)0%
Adsorption isotherms — Langmuir, Freundlich and BET — describe how much gas or solute a surface holds as pressure or concentration rises, and each one encodes a different physical picture of what is happening at the surface. This 2D canvas simulator plots all three models on a single overlaid graph so their curve shapes can be compared directly: Langmuir's hard monolayer plateau, Freundlich's open-ended power-law climb, and BET's upward multilayer divergence near saturation. Independent sliders for every model's parameters (saturation capacity, affinity constant, heterogeneity exponent, and the BET constant) reshape each curve in real time, while a synchronized surface-coverage animation shows the focused model's own picture of molecules filling — and, for BET, stacking on top of — the surface as relative pressure sweeps from 0 to 1.