There are two common methods for the experimental determination of adsorption enthalpies of surfactants on solid surfaces in aqueous solution, either directly by calorimetry or indirectly by using a Clausius-Clapeyron equation. The present paper is the second part of a two-part contribution dealing with a comparison of both methods. In this part calorimetric results on the adsorption of a nonionic (n-octyltetraoxyethylene) and a cationic (cetylpyridinium chloride) surfactant on a wide pore silica gel are presented for different temperatures between 25 and 40 degrees C. For the fast adsorbing nonionic surfactant good quantitative agreement between the isosteric and calorimetric differential molar heats of adsorption (13.5 +/- 1 kJ/mol) is found above a relative surface coverage of 0.1. For the cationic surfactant the agreement between the isosteric and the calorimetric enthalpy data is more qualitative. The reason is probably that the adsorption rate is too slow to reach equilibrium in the calorimetric experiments (flow calorimetry). The differential molar enthalpies of adsorption of the cationic surfactant are exothermic. Advantages and limitations of the calorimetric and isosteric method are discussed.