The Noble Gases Helium to Radon

With Ar, the effect tends to be borderline. With Kr, all values of JV ( h and b series) decrease with rise in temperature. Saylor and Battino give Na values for Xe and the b series. These show a marked decrease with rise in t°C. 

These workers found that of the several physical properties tried, polarizability of the gases yielded the best fit against the log plot for He to Xe. In Fig. 61,1 show 

Allowing for limitations of the data, it is seen that they fit into the essential pattern for the gaseous hydrocarbons. At 0°C the value for n-hexane is a little higher than the R-line value, whereas the value for aniline is at the low end still lower is the value for glycerol, and that for water even lower. The series of n-carboxylic acids shows a steady increase in Xr values, from Xr = 0.00162 for HCOOH at 25 C, pn 760 mm up to 0.0617 for C7H15COOH, a value approaching the R-line one of 0.0665 (Fig, 62). The plot is almost linear up to C5 and then begins to flatten. The more restricted series of n-alcohols, MeOH to n-BuOH, also show an almost linear plot. See refs. 4, 30, 31, 123, 330. 

For each gas, the Na. value for water is less than for all other examined liquids (see Table 7). The Na values for the same t°C (about 20-25°C) and Pa = 760 mm Hg are all on the left of the R-line for helium. Cady et. al. (1922) gave their data for 

The outstanding feature is the structure of water and its resistance to change in structure. Whereas the noble gases have no shared electrons, the hydrocarbon gases CH4 to m-C4Hio have no unshared ones. The Na (water) values for these hydrocarbon gases form a close cluster well on the left of the R-line for methane. 

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