Compilation of thermal properties of hydrogen in its various isotopic and ortho-para modifications.

New developments in science and industry are aided by accurate knowledge of the behavior of important substances. The great abundance of chemical processes and comX pounds in which hydrogen is involved make it of particular interest. The experimental and derived data presented here for hydrogen extend over a large range of temperature. Low temperatures are required for the liquid and solid, and moderate and high temperatures occur in chemical reactions. The available thermal data for H2, HD, and D2 in solid, liquid, and gaseous states have been brought together, including the distinctive properties of ortho and para forms of H2 and D2. Some data not previously published have been added. The thermal data include thermodynamic functions for the ideal gas state, equilibrium constants, data of state, viscosity, and thermal conductivity with dependence on the pressure, vapor pressure* solid-liquid equilibria, specific heats, and latent heats. Values of state derivatives useful in thermodynamic calculations have been given for normal hydrogen, and. the related differences between thermodynamic functions for real and ideal gas states have been evaluatedA temperature entropy diagram for normal H2 in the range of experimental data is also given. The compiled thermal properties of hydrogen are presented in 38 tables, 33 graphs, and numerous equations. The sources of the data have been given in an extensive bibliography.