Vapor pressure calibration data

See TUPAC Recommended Data for Vapor Pressure Calibration ... 

Source "lUPAC Recommended Data for Vapor Pressure Calibration," in CRC Handbook of Chemistry and Physics (1913-1995), 75th Edition (Special Student Edition), editor-in-chief, David R. Lide, 6-109 (Boca Raton, FL CRC Press, 1994). 

The molecular weight distributions of the oligomers were determined by means of gel permeation chromatography. These were done by Dr. Julian F. Johnson who was then at the Chevron Research Company. A Waters Analytical G.P.C. Model 300 was used. A combination of one 100,000 R, one 15,000 A, one 100 R, and one 45 R column was used. The columns were calibrated with normal alkanes and monodisperse polystyrenes. Samples were dissolved in toluene to obtain 60 mg/100 ml concentration they were eluted with toluene at a flow rate of 1 ml per minute at room temperature. The results were machine-computed to obtain relative molecular weights. From these, absolute values of the molecular weights were obtained by means of scaling factors calculated from experimental viscosity or vapor pressure osmometry data. The calibration curve is shown... 

See Vapor Pressure of Fluids at Temperatures below 300 K See TUPAC Recommended Data for Vapor Pressure Calibration ... 

To prove that this method can be applied also to solids with strong ionic bonding, NaCl was investigated as an example. Also in this case an aluminia Knudsen cell was used, the orifice diameter was calibrated with gold. Figure 69 shows a graphical presentation of the vapor pressure data obtained, compared with data from the literature (Kelly)68. ... 

To construct the adsorption isotherm, the adsorption, desorption, and calibration cycle shown in Fig. 15.11 is repeated for each data point required. Errors are not cumulative since each point is independently determined. Relative pressures corresponding to each data point are established by measuring the saturated vapor pressure using any of the preceding methods or by adding 15 torrs to ambient pressure. Thus, if X is the mole fraction of adsorbate in the flow stream, the relative pressure is given by... 

In addition to the estimated properties, we measured the thermochemistry of several important vapor species. These measurements were conducted in a Knudsen effusion cell using special line-of-sight vaporization under subambient pressures with flowing O2 and H2O vapor mixtures [4]. The gaseous species over silica [5], manganese oxide [6], lanthana, alumina, and palladium metal were detected and relative partial pressures measured as a function of temperature. These vapor pressure measurements were calibrated by using the known metal atom or binary metal oxide volatility as a calibration source. Oxide species concentrations were measured relative to that of a reference compound, e.g., metal atom. The identification of oxide and hydroxide compounds was facilitated by Ae technique of threshold electron ionization [7]. These data were then evaluated using estimated entropy functions and the third law temperatures. 

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