Thermodynamics!! Finding a fundamental equation. This is the question: "While he Gibbs free energy G is the fundamental function of the atral variables (T,p,N), (T=temperature, p=pressure, N=number of molecules), growing biological cells often regulte not the numbers of molecules N, but the chemical potentials μ. That is, they control concentrations. What is the fundamental function Z of natural variables (T,p,μ)? I know a few equations that deal with Gibbs free energy: G=H-TS G=[tex]\sum[/tex]μN Basically, I have no idea where to start with this problem. If anyone can give me a push in the right direction that would be much appreciated!!