Critical temperatures, pressures, and volumes of hydrogen, deuterium, and hydrogen deuteride

The cri t ical temperat ures, press ures, and vo lumes of H 2 , HD, a nd Dz have bee n determi ned by m easurin g shor t sections of P-F isotherms in t he neighborhood of t he cri t ical poin ts.T he H 2 a nd Dz sa mples wer e ca taly zed to or tho-para equilibrium at 20.4° K and a re des ignated e-H z a nd e-D.. Fo r e-H z t he values found a re T , = 3 2.994 o K, P , = 12.770 atm a nd 1', = 65.5 cm3 mole-I.Fo r HD the corresponding values a re 35.908°K , 14.645 at m, and' 62.8 cm3 mole-I; for e-Dz t he values a re 38.26Zo K , 16. 282 atm, an cl 60. 3 cm3 m ole-I.A m et hod of correlatin g isotherm data fo r different s ubstances, based on t he use of g rap hs of log P " ers us log Y, is desc ri bed.52.07 18.6b 32.