P-T- ( = composition) isobars have been measured using an equilibrate-quench-analyze technique. The metal samples were single crystals of super-pure palladium. It has been found that, in the composition range investigated, the partial thermodynamic functions of the dissolved H-atoms did not depend on composition. However, a strong temperature dependence was found. The present results are in excellent agreement with previous measurements using polycrystalline Pd at high temperatures, but strong deviations are found at low temperatures.