Vapour phase composition and activities for the molten PbBr2+KBr system

1968 ◽  
Vol 21 (3) ◽  
pp. 583 ◽  
Author(s):  
H Bloom ◽  
JW Hastie
Keyword(s):  
Mass Spectrometry ◽  
Phase Composition ◽  
Vapour Phase ◽  
Lead Bromide ◽  
Transpiration Method ◽  
Entropy Of Formation ◽  
Enthalpy And Entropy ◽  
Complex Ion

Vapour pressures above molten PbBr2+KBr mixtures have been measured over a range of temperatures by a transpiration method. The vapours have been investigated also by mass spectrometry and the presence of the complex KPbBr3 has been established. The enthalpy and entropy of formation of this compound from PbBr2(g) and KBr(g) are similar to values obtained for the analogous chloride species. By combining the results of both methods, the true activities of lead bromide in the melt have been calculated as a function of composition, and the results have been interpreted to show that PbBr3 is the major complex ion present in the molten mixtures.

Vapour phase composition and activities for the molten PbCl2 + NaCl system

1972 ◽  
Vol 25 (10) ◽  
pp. 2077 ◽  
Author(s):  
H Bloom ◽  
SR Richards ◽  
DJ Williams
Keyword(s):  
Mass Spectrometry ◽  
Phase Composition ◽  
Binary Systems ◽  
Vapour Phase ◽  
The Other ◽  
Regular Solutions ◽  
Alkali Chloride ◽  
Transpiration Method ◽  
Alkali Chlorides ◽  
The Enthalpy Of Formation

Vapour pressures of molten PbCl2 + NaCl mixtures have been measured a.t 1071 K by a transpiration method. The vapours have also been investigated by mass spectrometry and the complex NaPbCl3 has been established. The enthalpy of formation of this complex from NaCl(g) and PbCl2(g) has been determined and the equilibrium constant for its formation has been estimated. Enthalpies of vaporization of NaCl and PbC12 and the enthalpy of dimerization of NaCl(g) agree with published results. The mass spectrometry results have enabled corrections to be made to measured activities of PbCl2 from the transpiration results, for errors due to the NaPbCl3 complexes. The activity values so determined are compared with those for other molten binary systems involving lead and alkali chlorides. The PbCl2 + NaCl system (like the other PbCl2 + alkali chloride systems except PbCl2 + LiCl) does not behave as regular solutions.

Vapour-liquid equilibrium. The effect of temperature on the equilibrium vapour phase composition and on the azeotropic point composition

1991 ◽  
Vol 56 (4) ◽  
pp. 745-749 ◽  
Author(s):  
Josef P. Novák ◽  
Jaroslav Matouš ◽  
Petr Voňka
Keyword(s):  
Phase Composition ◽  
Vapour Phase ◽  
Butyl Alcohol ◽  
Effect Of Temperature ◽  
Calorimetric Data ◽  
Liquid Equilibrium ◽  
Azeotropic Point ◽  
Tert Butyl Alcohol ◽  
Point Composition ◽  
Heats Of Vaporization

On the basis of analysis of calorimetric data, it is shown that the tert-butyl alcohol(1)-water(2) system exhibits the non-monotonous dependence of the equilibrium vapour phase composition on temperature which is reflected in the non-monotonous dependence of azeotropic composition on temperature. This behaviour is conditioned primarily by the fact that the molar heats of vaporization of both the substances have the same value at the temperature of 57°C. From the values of heats of vaporization of C3 and C4 alcohols and water it is evident that the analogous behaviour occurs also in aqueous systems of these alcohols at common temperatures.

scholarly journals Isothermal vapour-liquid equilibria in cyclohexanone + dichloroalkane binary mixtures at temperatures from 298.15 to 318.15K

2011 ◽  
Vol 76 (2) ◽  
pp. 305-315 ◽  
Author(s):  
Dana Dragoescu ◽  
Alexandru Barhala ◽  
Mariana Teodorescu ◽  
Daniela Chiscan
Keyword(s):  
Phase Composition ◽  
Liquid Phase ◽  
Binary Mixtures ◽  
Activity Coefficients ◽  
Virial Coefficient ◽  
Vapour Phase ◽  
Composition Data ◽  
Gibbs Energies ◽  
Significant Difference ◽  
Liquid Phase Composition

The vapour pressures of binary mixtures of cyclohexanone + dichloroalkane (1,3-dichloropropane and 1,4-dichlorobutane) were measured at temperatures between 298.15 K and 318.15 K. The vapour pressures vs. liquid phase composition data were used to calculate the activity coefficients of the two components and the excess molar Gibbs energies GE for the mixtures, using the Barker method and the Redlich-Kister, Wilson, NRTL and UNIQUAC equations, taking into account the vapour phase imperfection in terms of the 2nd virial coefficient. No significant difference between the GE values obtained with these equations was observed.

scholarly journals Determination of Volatile N-Nitrosamines in the Vapour Phase of the Smoke from Various Tobacco Products

1975 ◽  
Vol 8 (3) ◽  
Author(s):  
P.J. Groenen ◽  
M.C. ten Noever de Brauw
Keyword(s):  
Mass Spectrometry ◽  
Vapour Phase ◽  
Tobacco Products ◽  
Flame Ionization ◽  
Capillary Glc ◽  
The One ◽  
The Individual ◽  
Positive Results ◽  
Whole Smoke

AbstractVolatile N-nitrosamines were determined in the vapour phase of tobacco smoke after accumulation of Iarge vapour samples on to a cooled capillary GLC column. Detection was effected by computerized mass spectrometry and by a nitrogen-specific detector. Five different tobacco products were studied with mass spectrometry for the presence of eight individuaI nitrosamines. The result was negative thirty-nine times and positive only once. Initially, the detection Iimit for the individual nitrosamines was 2 ng per 20-55 mI vapour injection; during this study the effective detection limit was Iowered for some of the compounds by a further twofold to fivefold increase of the vapour volume analysed. The one nitroso compound identified positively and unambiguously was N-nitrosopiperidine in the smoke from the American blend cigarettes. It amounted to about 5.6 ng in the vapour phase of the smoke of one cigarette. The partition of nitrosamines between vapour phase and particulate phase is not known, but amounts of more than 1 µg of dimethylnitrosamine or nitrosopiperidine in the whole smoke of one cigarette as found by some authors, seem improbably high. It is shown in this paper that exclusive use of the alkali flame ionization detector for nitrosamine determinations would have led to false-positive results, especially for dimethylnitrosamine.

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