Theory of vapor pressure osmometry when ambient solvent vapor is unsaturated

Kamide, Kenji; Sugamiya, Ken; Nakayama, Chozo

doi:10.1002/macp.1970.021330108

Cited by 10 publications

(3 citation statements)

References 4 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…The VPO equation, eq , can be derived from a mass and heat transfer balance on the thermistors with several simplifying assumptions. Eq below shows the result of that derivation for the steady-state VPO signal from the work of Kamide et al This extended form of eq shows the sources of inaccuracy clearer and also illustrates the difficulty in quantifying them. (The symbols for eq are explained in Table .…”

Section: Resultsmentioning

confidence: 99%

Accuracy, Repeatability, and Limitations for Determination of Chemical Activities from Vapor Pressure Osmometry

Gray

Nilsson

2018

Anal. Chem.

View full text Add to dashboard Cite

Vapor pressure osmometry presents a convenient method to measure chemical activity. The work presented here was carried out to provide confidence in using this technique for a VPO model that does not utilize the "hanging-drop" method. While validation studies are available for certain models of vapor pressure osmometers, none were located for the UIC Jupiter 833 osmometer. This study addresses that need by providing a comparison between original experimental data on sodium chloride, calcium chloride, and sodium sulfate solutions to values calculated using the Pitzer equations. A comparison is also made for experimental data on sucrose with a literature correlation. This study briefly reviews the assumptions going into the equation used to relate the osmometer signal to the diluent activity in order to identify potential sources of the error and the noise in the data. The experimental data shows that the UIC 833 osmometer yields diluent activity values accurate to an average of 0.02%, allowing calculation of osmotic coefficients and solute activity coefficients. Further studies need to be conducted on the accuracy at concentrations above 1.4 m. Qualitatively, however, comparison suggests the UIC Jupiter 833 osmometer yields more scatter in the experimental data than the Knauer instruments. Using more uniform mesh caps on the thermistors could possibly reduce that scatter. Finally, we show that replacing the glass thermistors with in-house made thermistors with Teflon incorporated in the structure give reproducible results and that certain modifications to the design are possible without losing accuracy in the measurements.

show abstract

Section: Resultsmentioning

confidence: 99%

Accuracy, Repeatability, and Limitations for Determination of Chemical Activities from Vapor Pressure Osmometry

Gray

Nilsson

2018

Anal. Chem.

View full text Add to dashboard Cite

show abstract

“…This method, developed originally for the estimation of molecular mass, has been well-established. − The currently used thermistor-type vapor pressure commercial osmometers give the solvent activities rapidly, but they are usually less accurate than the alternative vapor-pressure methods . Nevertheless, vapor pressure osmometry is a suitable technique for measuring the solvent activity at a low molality.…”

Section: Experimental Methodsmentioning

confidence: 99%

Measurement of the Osmotic Coefficients in Aqueous Solutions of Imidazolium Ionic Liquids ([C_nmim]Cl or [C_nmim]Br, n = 4, 6, 8) Over a Wide Salinity Range at 298.15 K

Korchak,

Safonova,

Victorov

2023

J. Chem. Eng. Data

View full text Add to dashboard Cite

The goal of this work is to provide accurate and detailed experimental data on the osmotic coefficients and the activity of water for the binary aqueous solutions of ionic liquids [C n mim]Cl and [C n mim]Br (n = 4, 6, and 8), covering the broad range of salinity up to 10 mol•kg −1 . Such data form the basis for the thermodynamic description of the system, and are needed, in particular, for the estimation of parameters of thermodynamic models. Our data supplement and extend to a broader concentration range the existing literature data on the studied systems at 298.15 K. The systematic presentation of the data includes the method used, the conditions, the concentration range, and the estimates of the experimental errors. To help in the assessment of the data quality, we compare all of the available data sets. Using vapor pressure osmometry and isopiestic methods to perform experiments, we discuss possible sources of error and explain in every detail the construction of the apparatus designed in our lab to reduce the experimental errors to a minimum. For [C 8 mim]Cl and [C 8 mim]Br, known to form micelles in aqueous solutions, we estimate the critical micelle concentration from our experimental data on the osmotic coefficients and the activity of water.

show abstract

“…Apparent virial coefficients obtained b y the VPO are not, in general, in good agreement with those obtained b y the membrane osmometry2>3). Thereafter, KAMIDE et al 4) pointed out t h a t the ambient vapor is unsaturated in the VPO apparatus commercially available. A new VPO theory, in which the unsaturation of ambient vapor pressure was taken into account, has been presented as a generalization of the KAMIDE and SANADA theory4).…”

Section: Introductionmentioning

confidence: 99%

Theory of vapor pressure osmometry on ternary mixture

Kamide

Fujishiro

1971

Makromol. Chem.

Self Cite

View full text Add to dashboard Cite

The theory of vapor pressure osmometry on mixtures of the solute of type B and the solute of type C in a single solvent of type A is eslablished as an extension of the theory of a single solute/a single solvent system by KAMIDE and SANADA. The temperature difference a t steady state, (T -TO)^, between a solution drop consisting of solute B/solute C/ solvent A and a solution drop consisting of solute B/solvent A (the molar ratio of solvent A to solute B, designated as s, is a constant) in ambient saturated vapor phase of solvent A, which is in equilibrium with the solution of solute B in solvent A, is calculated. I n deriving corresponding equations the solution was regarded as a regular solution and the molecular sizes of the common solute B and the solvent A were assumed to be not so different from each other. For the ternary system, the interaction parameters, expressed by XIJ, are included in the calibration parameter. However, in general, as s of the composition A/B > 0.99, the correction term can almost be neglected, if the ratio of molar volumes V: / V: (m,) does not exceed ten. Therefore, the experimental dath uuculllvu uuch a system can be treated in a similar manner with that for the binary system. ZUSAMMENFASSUNG: Die Theorie der Dampfdruckosmometrie wird, in Erweiterung der Theorie von KAMIDE und SANADA, welche das System geloster Stoff/Losungsmittel behandelt, fur Losungen, in denen gleichzeitig ein Stoff des Typs B und ein Stoff des Typs C im Losnngsmittel A enthalten sind, aufgestellt. Berechnet wird die Temperaturdifferenz in stationarem Zustand (Tzwischen einem Losungstropfen, bestehend aus gelostem Stoff B/gelostem Stoff C/Losungsmittel A, und einem Losungstropfen, bestehend aus gelostem Stoff B/Losungsmittel A (der Molenbruch der Stoffe A und B, mit s bezeichnet, ist konstant), welche sich in der mit der Losung von B in A im Gleichgewicht stehenden Sattigungsdampfphase von A befinden. Bei der Ableitung korrespondierender Gleichungen wurde die Losung als regular angesehen und angenommen, daa die MolekulgroBe des gemeinsam gelosten Stoffes B sich von der des Losungsmittels nicht wesentlich unterscheidet. Die durch XIJ ausgedriickten Wechselwirkungsparameter werden fur die Dreistoffsysteme im Eichparameter miterfaat. Da im allgemeinen jedoch s > 0,99 ist, kann der Korrektionsterm nahezu vernachlassigt werden, sofern das Verhaltnis der Molvolumina Vc/V* den Wert 10 nicht uberschreitet. Aus diesem Grund konnen die experimentell erhaltenen Werte eines solchen Systems in ahnlicher Weise wie die fiir Zweistoffsysteme ausgewertet werden.

show abstract

Theory of vapor pressure osmometry when ambient solvent vapor is unsaturated

Cited by 10 publications

References 4 publications

Accuracy, Repeatability, and Limitations for Determination of Chemical Activities from Vapor Pressure Osmometry

Accuracy, Repeatability, and Limitations for Determination of Chemical Activities from Vapor Pressure Osmometry

Measurement of the Osmotic Coefficients in Aqueous Solutions of Imidazolium Ionic Liquids ([C_nmim]Cl or [C_nmim]Br, n = 4, 6, 8) Over a Wide Salinity Range at 298.15 K

Theory of vapor pressure osmometry on ternary mixture

Contact Info

Product

Resources

About

Theory of vapor pressure osmometry when ambient solvent vapor is unsaturated

Cited by 10 publications

References 4 publications

Accuracy, Repeatability, and Limitations for Determination of Chemical Activities from Vapor Pressure Osmometry

Accuracy, Repeatability, and Limitations for Determination of Chemical Activities from Vapor Pressure Osmometry

Measurement of the Osmotic Coefficients in Aqueous Solutions of Imidazolium Ionic Liquids ([Cnmim]Cl or [Cnmim]Br, n = 4, 6, 8) Over a Wide Salinity Range at 298.15 K

Theory of vapor pressure osmometry on ternary mixture

Contact Info

Product

Resources

About

Measurement of the Osmotic Coefficients in Aqueous Solutions of Imidazolium Ionic Liquids ([C_nmim]Cl or [C_nmim]Br, n = 4, 6, 8) Over a Wide Salinity Range at 298.15 K