Thermodynamic functions of germanium tetrabromide over the temperature range 5-315 K

The temperature dependence of the heat capacity of germanium tetrabromide G eBr4 was studied for the first time using low-temperature adiabatic calorim etry in the temperature range from 5 to 315 K. The thermodynamic functions, namely, the absolute entropy, the enthalpy difference, and the Gibbs energ y function, were calculated based on the results obtained. The following st andard values were found: S degrees(298.15 K) = 247.4 +/- 0.2 J/(mol K), H degrees(298.15 K) - H degrees(0) = 29 360 +/- 30 J/mol, and Phi degrees(298 .15 K) = 148.9 +/- 0.2 J/(mol K). The melting of germanium tetrabromide was studied, and thermodynamic characteristics of the process were determined: T-m = 299.27 +/- 0.01 K, Delta(m)H degrees(T-m) = 12850 +/- 30 J/mol, and Delta(m)S degrees(T-m) = 42.94 +/- 0.05 J/(mol K).