Question: a common model for polymer configurational entropy considers each link...
A common model for polymer configurational entropy considers each link in the polymer chain backbone to have only three possible values (the three staggered angles, 60, 180, 300) of χ, the dihedral angle, all with the same probability and all independent of each other. For a polymer with N monomer units, there are N-1 links. One “configuration” of the polymer means one possible choice for all the N-1 dihedral angles, χ1,χ2,...,χN-1.
b) Find an expression for the entropy change in going from a state where only one configuration is allowed to a state where all configurations are allowed.