Abstract:
The quantity (1/λ1)(dλ12/dx2)(x2→ 0), where λ1 is the thermal conductivity of hydrogen or helium and λ12 is the thermal conductivity of one or the other of these gases containing a limitingly small mole fraction x2 of an organic vapour, is studied experimentally. The above quantity is closely related to the calibration coefficient for the vapour in a catharometer, especially as used in gas chromatography. The discussion shows that if the quantity is used to determine collision diameters of the organic molecules on the assumption that the internal structure has little effect, then the values so obtained correlate well with similar values calculated similarly from corresponding measurements of(1/η1)(dη12/dx2), where η is viscosity. Collision diameters obtained from either measurement correlate well with values reported in the literature calculated from transport coefficients of the pure organic vapours.
