Vapour pressures of aqueous solutions of (Ag,Tl,Cd)NO3 at 98.5 °C. II. Henry's law and excess free energy

1978 ◽  
Vol 56 (5) ◽  
pp. 635-637 ◽  
Author(s):  
Marie-Christine Abraham ◽  
Maurice Abraham ◽  
James Malcolm Sangster
Keyword(s):  
Free Energy ◽  
Activity Coefficient ◽  
Excess Free Energy ◽  
Cadmium Content ◽  
Henry's Law ◽  
Henry’S Law ◽  
Finite Concentration ◽  
Pass Through ◽  
Extremum Value ◽  
Bet Equation

Curves of the water activity coefficient γw have been obtained as a function of water mole fraction in the mixtures AgNO3 + TlNO3 + Cd(NO3)2 + H2O at 98.5 °C. It has been shown, in this study, from the BET equation itself and verified experimentally, that γw may pass through an extremum value for certain systems. The position of such an extremum near the fused salt end of the concentration scale can explain the appearance of a 'practical' Henry's law in a finite concentration range. The curves of the excess free energy of the system undergo rather unusual changes of shape as the cadmium content of the melt is varied.

596. Steam distillation of taints from cream: I. Theoretical considerations and properties of the reference substances, diacetyl and acetoin

1955 ◽  
Vol 22 (3) ◽  
pp. 311-327 ◽  
Author(s):  
F. H. McDowall
Keyword(s):  
Activity Coefficient ◽  
Partition Coefficient ◽  
Steam Distillation ◽  
Pure Substance ◽  
Dilute Solution ◽  
Henry's Law ◽  
Henry’S Law ◽  
Influence Of Water ◽  
Equilibrium Relationships ◽  
Theoretical Considerations

The rate of removal of a dissolved tainting substance from cream by steam-distillation treatment is dependent in part on the relative volatility (or boiling point) of the pure substance, in part on the temperature of steam distillation, and in part on the influence of water on the vapour pressure of the tainting substance in dilute solution (i.e. on the activity coefficient, γ).The application of Raoult's law and Henry's law to the problem of removal of taints from cream is discussed. For the dilute solutions commonly encountered in cream Henry's law can be expected to apply.The equilibrium relationships for diacetyl and acetoin used as reference substances in investigations on cream-deodorizing equipment have been determined. The equilibrium coefficient for diacetyl in water at concentrations up to 50 p.p.m. in the liquid, as measured by the continuous equilibrium vaporization method, is 39·3. With rise in concentration above 50 p.p.m. in the liquid the coefficient decreases. At 100 p.p.m. it is 32 and at 1000 p.p.m. it is 20. The coefficient for acetoin in water at all concentrations up to 1·2% in the liquid is constant at 1·29. The activity coefficient for diacetyl in concentrations up to 50 p.p.m. was found to be 26·4 and for acetoin at concentrations up to 1·2%, 5·4.For diacetyl the solubility partition coefficient as between butterfat and water rises from 0·47 at 100° F. to 0·74 at 180° F. For acetoin the partition coefficient remains constant at 0·18–0·19 over this range of temperatures. Correspondingly diacetyl is removed equally easily from butterfat and from water, whereas acetoin steam-distils much more readily from butterfat than from water.

scholarly journals Henry's law constants of polyols

2014 ◽  
Vol 14 (23) ◽  
pp. 12815-12837 ◽  
Author(s):  
S. Compernolle ◽  
J.-F. Müller
Keyword(s):  
Solid State ◽  
Activity Coefficient ◽  
Vapour Pressure ◽  
Infinite Dilution ◽  
Hydroxyl Groups ◽  
Henry's Law ◽  
Hydroxy Acids ◽  
Henry’S Law ◽  
Henry’S Law Constants ◽  
Henry's Law Constants

Abstract. Henry's law constants (HLC) are derived for several polyols bearing between 2 and 6 hydroxyl groups, based on literature data for water activity, vapour pressure and/or solubility. While deriving HLC and depending on the case, also infinite dilution activity coefficients (IDACs), solid state vapour pressures or activity coefficient ratios are obtained as intermediate results. An error analysis on the intermediate quantities and the obtained HLC is included. For most compounds, these are the first values reported, while others compare favourably with literature data in most cases. Using these values and those from a previous work (Compernolle and Müller, 2014), an assessment is made on the partitioning of polyols, diacids and hydroxy acids to droplet and aqueous aerosol.

Thermodynamics of the Effect of Alloying Additions on In-Situ Reaction to Synthesize TiC/Mg Composites

2007 ◽  
Vol 351 ◽  
pp. 161-165
Author(s):  
Wei Cao ◽  
Cong Fa Zhang ◽  
Tong Xiang Fan ◽  
Di Zhang
Keyword(s):  
Free Energy ◽  
Activity Coefficient ◽  
Phase Formation ◽  
Chemical Reaction ◽  
Excess Free Energy ◽  
Alloying Element ◽  
Alloying Additions ◽  
Molten Magnesium ◽  
Particulate Reinforced

The effect of the alloying element additions on in-situ chemical reaction to synthesize particulate reinforced TiC/Mg composites was evaluated from the viewpoint of thermodynamics. The influences of alloying elements on the changes of the activity coefficient and the excess free energy in molten magnesium were calculated. The results show that additions, such as Nd, La, Ca, Cu and Zr can promote TiC formation, at the same time hinder the brittle TiAl3 phase formation.

scholarly journals Henry's law constants of polyols

2014 ◽  
Vol 14 (9) ◽  
pp. 13529-13559 ◽  
Author(s):  
S. Compernolle ◽  
J.-F. Müller
Keyword(s):  
Solid State ◽  
Activity Coefficient ◽  
Vapour Pressure ◽  
Infinite Dilution ◽  
Hydroxyl Groups ◽  
Henry's Law ◽  
Hydroxy Acids ◽  
Henry’S Law ◽  
Henry’S Law Constants ◽  
Henry's Law Constants

Abstract. Henry's law constants (HLC) are derived for several polyols bearing between 2 and 6 hydroxyl groups, based on literature data for water activity, vapour pressure and/or solubility. Depending on the case, infinite dilution activity coefficients (IDACs), solid state pressures or activity coefficient ratios are obtained as intermediary results. For most compounds, these are the first values reported, while others compare favourably with literature data in most cases. Using these values and those from a previous work (Compernolle and Müller, 2014), an assessment is made on the partitioning of polyols, diacids and hydroxy acids to droplet and aqueous aerosol.

Sign in / Sign up

Export Citation Format

Share Document