Freundlich Adsorption Isotherm

θ = fractional coverage, a , b = constants, p = pressure

  When describing adsorption onto a surface a parameter often used is the fractional coverage θ , defined as the ratio of occupied adsorption sites to available adsorption sites. The variation of θ with pressure at a given temperature is called an adsorption isotherm. In some cases the variation is as given above.