High Temperature Properties of Sodium.

Interaction second virial coefficients for sodium-inert gas mixtures

“…Experimental values for the primary second virial coefficients 6t1(7) have been published by Ewing et al (17) and calculated values have been given by Sannigrahl and Mohammad (21). For a list of 622 (7) I It is now a straightforward task to evaluate B(T) coefficients for any particular mixture of Na vapor and inert gases using eq 4.…”

“…Several theoretical calculations have also been reported (11)(12)(13)(14)(15). In addition, thermodynamic properties and second virial coefficients for pure alkali vapors (16,17) and pure inert gases (16,18) are available in the literature, but, to our knowledge, no alkali-inert gas interaction virial coefficients have been reported. The purpose of this paper is to present calculated values of interaction second virial coefficients for Nainert gas mixtures that can then be used to calculate the thermodynamic properties of such mixtures from knowledge of the properties of the pure component gases.…”

Molecular association in sodium, potassium, and cesium vapors at high temperatures

“…where N is mole fraction, p is pressure, and n may be 2, 3, or 4 for the dimeric, trimeric, and tetrameric reactions.…”

“…If PVT data are of sufficiently high precision, a distinction between trimer and tetramer can be made with eq 3. If, in a vapor mixture, species of molecular weight higher than the trimer are not present, eq 3 (by setting fa = 0) reduces to fa' -2fa2p3 = fa + 2fap (4) Likewise, if the trimeric species is taken as insignificant, the same equation reduces to fa' + 2 fafap3 = fa + Sfap2 (5) It follows from these equations that a linear relationship between (fa' -2fa2p3) and p implies the existence of trimer, while a linear relationship between (fa' + 2fafap3) and p2 implies the existence of tetramer.…”