ABSTRACT
Now we come to the problem of calculating the thermodynamic properties of gases. This differs from what we have done for solids primarily in the method of counting the stationary states of the assembly. In solids the molecules could be considered as distinguishable in the sense that, being localised, their average positions served to identify them. In gases this is no longer true and we must take account of the fundamental indistinguishability of the molecules of our assembly.
