Using the powder x-ray diffraction method, the phase diagrams of the b
inary systems Ar-Xe, Kr-Xe, and Kr-CO have been studied. The molar vol
umes of these solutions versus temperature and composition have been d
etermined within the homogeneity regions. A considerable deviation of
the solubility from the Hume-Rosery rules (which is valid for metal al
loys) has been found.