1. Consider a heterogeneous surface of Area A. half of the surface is one type and the other half is of another type. This surface is exposed to a gas at pressure P, and temperature T. The molecules interact with the surface via 6-12 potential. The depth of the potential minima for the surface sites are 1 and 2, respectively. The diameter of the molecule is . Using the above information and/or invoking any other information you need, find out how the total adsorbed amount depends on the pressure of the gas.