Chemical potentials and related thermodynamics of sodium-ammonia solutions

Data on the temperature and composition dependence of the chemical potential of Na in Na–NH3 solutions obtained from an electrochemical cell are reported. The cell used a bridge electrode of sodium beta-alumina. A variety of thermodynamic parameters are calculated and estimates are given for the critical exponents α, γ, and δ. Particular attention is paid to the concentration fluctuations 〈(Δ x)2〉 which provide indications of clustering in these and other solutions.