Orthobaric Surface Tensions Research Articles

Surface Tension of Pure Hydrocarbons

A new correlation scheme for the surface tension of a homologous series of pure liquid hydrocarbons, as a function of molecular weight and temperature, is presented. Using orthobaric surface tension data from literature for four homologous series of hydrocarbons, i.e., n-alkanes, 1-alkenes, cycloalkanes, and aromatics, the adjustable parameters for two new surface tension equations are obtained individually for each series. The agreement between experimental values and those calculated with the two new generalized surface tension equations is very good, i.e., the temperature and molecular weight dependences of surface tension are well reproduced.

Thermodynamics of linear dimethylsiloxane–perfluoroalkane mixtures Part 3.—Orthobaric surface tensions of hexamethyldisiloxane–, octamethyltrisiloxane– or decamethyltetrasiloxane–tetradecafluorohexane near the upper critical endpoint

The orthobaric surface tensions of three dimethylsiloxane–perfluoroalkane mixtures: hexamethyldisiloxane–, octamethyltrisiloxane– and decamethyltetrasiloxane–tetradecafluorohexane have been measured at temperatures close to the upper critical solution temperatures. All three mixtures are normal in the sense that the more volatile component has the lower surface tension. The surface tension isotherm closest to the critical endpoint displays a characteristic horizontal inflection at a composition very close to the critical composition previously determined from the liquid–liquid coexistence curve. The incidence of negative aneotropy is distinct in the hexamethyldisiloxane–tetradecafluorohexane mixture and wholly absent in the decamethyltetrasiloxane–tetradecafluorohexane mixture with the mixture containing octamethyltrisiloxane intermediate in behaviour. The first mixture displays both azeotropy (predicted via the application of the regular solution theory of mixtures) and aneotropy, the second azeotropy and rather indistinct aneotropy and the third mixture neither azeotropy nor aneotropy; these observations emphasise that although vapour pressure and surface tension extrema often occur in mixtures simultaneously there is no theoretical necessity that they should do so. As in many other mixture properties there are great similarities between dimethylsiloxane–perfluoroalkane and alkane–perfluoroalkane mixtures, particularly those containing hexamethyldisiloxane or hexane.

Orthobaric surface tension of (tetrachloromethane + tetradecafluoromethylcyclohexane) in the critical region at temperatures from T= 303 K to T= 315 K

With a view to investigating the surface tensions of a (non-alkane+perfluoroalkane) mixture which, in a similar fashion to a typical (alkane+perfluoroalkane) mixture, displays large positive derivations from bulk ideality and large negative deviations from surface ideality, we have determined the orthobaric (gas + liquid) surface tension of tetrachloromethane at temperatures from 296 K to 323 K, and of (tetrachloromethane + tetradecafluoromethylcyclohexane) from T= 303 K to T= 315 K close to the upper critical solution temperature T UCS= 302.23 K. The surface tensions of the mixture display both large negative deviations from surface ideality and a close-to-horizontal inflection like that first predicted by Widom for the tension of the noncritical interface of a mixture at a critical end point. Incidentally, but no less interestingly, the mixture comprises substances of almost equal vapour pressure—and hence is neither normal nor non-normal in the sense of the Widom definition whereby a normal mixture is one in which the more volatile component is of lower surface tension, or tautness. It is surprising, therefore that the near-critical surface tension isotherms display an inflection of a nature more to be expected if the vapour pressures of the components were more different and tetradecafluoromethylcyclohexane were the more volatile.

Temperature dependence of the surface tension for binary mixtures ofn-butanenitrile +n-alkanes

The differential capillary-rise method was used to determine the orthobaric surface tension of binary liquid mixtures ofn-butanenitrile mixed withn-pentane,n-hexane, andn-heptane, throughout the composition range. at 293.15, 303.15, 313.15, 323.15, 333.15. and 343.15 K. Furthermore, the system withn-hexane was also studied al 263.15 K. i.e., 19 K above its upper critical solution temperature, over the whole composition range. For each binary system the surface tension changes regularly with both temperature and composition between the values of the pure components. The results are discussed in terms of deviations from surface ideality and related to the large positive deviations observed for bulk properties of the same systems.

Orthobaric surface tension of (methylcyclohexane + tetradecafluoromethylcyclohexane) in the critical region at temperatures from 320 K to 335 K

With a view to investigating further the surface tensions of (a hydrocarbon + a perfluorocarbon) in which neither component is aliphatic—and thus open to chain-flexibility effects—or aromatic—and thus dominated by specific interactions, we have studied the orthobaric (gas + liquid) surface tension of methylcyclohexane at temperatures from 293 K to 338 K, of tetradecafluoromethylcyclohexane from 298 K to 338 K, and of their mixture across the full composition range at temperatures from 320 K to 335 K close to the upper critical solution temperature, T UCS = 319.262 K. The mixture is normal in the sense that the more volatile component, tetradecafluoromethylcyclohexane, has the lower surface tension. Reflecting the occurrence of marked positive deviations from bulk-phase ideality, emphasized by the occurrence of positive azeotropy, the mixture displays marked negative deviations from surface ideality, just sufficient to yield aneotropy or surface azeotropy a few kelvins above T UCS. Near T UCS the isotherms display the inflection characteristic of the prediction of Widom's theory of surface tensions at the non-critical interface of a mixture close to an upper critical end point. The total surface segregation, although positive across the entire mole-fraction range, shows the signature of both the critical end point and the azeotrope.

The orthobaric surface tensions of the three binary mixtures formed by krypton, ethane and ethene

The surface tensions of krypton–ethane and krypton–ethene mixtures have been determined as a function of composition from 116.0 to 124.0 K and for ethene–ethane mixtures from 117.0 to 135.0 K. In each case the deviations from mole-fraction linearity are negative, although least so for the mixture of hydrocarbons. The results have been analysed in terms of a number of theories that take no explicit account of the quadrupole nature of the hydrocarbons. Agreement with simple theories could be achieved by some empirical corrections of the Berthelot and Lorentz combining rules. However, the values of these differ significantly from those obtained with similar treatments applied to the bulk properties of these mixtures.

A generalized equation for surface tension from the triple point to the critical point

A three-parameter generalized equation is proposed for surface tension from the triple point to the critical point. This equation not only fits the data well but also is good for interpolation between the normal boiling point and the critical point. This equation is also good for extrapolation to the triple point. This equation has been tested using the surface tension of water from the triple point to the critical point. The constants of this equation obtained using orthobaric surface tensions are given for a number of compounds. The isobaric surface tensions determined at a pressure of 1 atm do not differ significantly from the orthobaric surface tensions. Such data also have been used in obtaining equations from the triple to the critical point.

Cell for orthobaric surface tension measurements at low temperatures

An experimental technique to determine orthobaric surface tensions of both pure and mixed liquefied gases by the differential capillary rise method at cryogenic temperatures is described. The apparatus has been tested with measurements performed on the ethane+ethane system, from 117 to 135 K.

Surface tensions of (an alkanol + an alkane) 1. Propan-1-ol + heptane

The orthobaric surface tensions of (propan-1-ol + heptane) have been measured by the differential capillary-rise technique at 6 temperatures between 293.15 and 333.15 K. The isotherms are all concave upwards without minima. The relative adsorption over the whole range of compositions has been calculated from these results and previously published vapour pressures; the adsorption of the alkanol relative to the heptane is negative at all compositions. A new interpretation of the relative adsorption is suggested. The results are discussed in relation to the liquid-vapour phase diagram.

An improved method of determining surface tension at low temperatures

A novel method of measuring orthobaric surface tensions of liquids at low temperatures using the differential capillary rise method is described. Results are given for hexamethyldisiloxane from 220K to 370K.

Surface tension of perfluoropropane, perfluoro-n-butane, perfluoro-n-hexane, perfluoro-octane, perfluorotributylamine and n-pentane. Application of the principle of corresponding states to the surface tension of perfluoroalkanes

The orthobaric surface tensions of C3F8, n-C4F10, n-C6F14, C8F18, (C4F9)3N and n-C5H12 have been measured by the differential capillary-rise technique over various ranges of temperatures. The results for the perfluoroalkanes have been analysed in terms of the van der Waals equation, the Brock and Bird equation incorporating Pitzer's acentric factor and the phenomenological corresponding-states treatment of Patterson and Rastogi; the data are fitted with varying degrees of success. The phenomenological principle of corresponding states to which the surface tensions for the perfluoroalkanes conform is not identical to that for the n-alkanes and some other homologous series, but it is similar to it, in particular in the need for at least three reduction parameters.

The Orthobaric Surface Tensions and Thermodynamic Properties of the Liquid Surfaces of a Series of 1-Alkenes, C6 to C16, and of n-Decylcyclopentane, n-Decylcyclohexane and n-Decylbenzene

The Orthobaric Surface Tensions and Thermodynamic Properties of the Liquid Surfaces of a Series of 1-Alkenes, C₆ to C₁₆, and of n-Decylcyclopentane, n-Decylcyclohexane and n-Decylbenzene

The Orthobaric Surface Tensions and Thermodynamic Properties of the Liquid Surfaces of the n-Alkanes C5 to C18 - Correction

The Orthobaric Surface Tensions and Thermodynamic Properties of the Liquid Surfaces of the n-Alkanes C5 to C18 - Correction

The Orthobaric Surface Tensions and Thermodynamic Properties of the Liquid Surfaces of the n—Alkanes, C5 to C28

ADVERTISEMENT RETURN TO ISSUEPREVArticleNEXTThe Orthobaric Surface Tensions and Thermodynamic Properties of the Liquid Surfaces of the n—Alkanes, C5 to C28Joseph J. Jasper, E. Robert Kerr, and Frederick GregorichCite this: J. Am. Chem. Soc. 1953, 75, 21, 5252–5254Publication Date (Print):November 1, 1953Publication History Published online1 May 2002Published inissue 1 November 1953https://doi.org/10.1021/ja01117a033RIGHTS & PERMISSIONSArticle Views369Altmetric-Citations66LEARN ABOUT THESE METRICSArticle Views are the COUNTER-compliant sum of full text article downloads since November 2008 (both PDF and HTML) across all institutions and individuals. These metrics are regularly updated to reflect usage leading up to the last few days.Citations are the number of other articles citing this article, calculated by Crossref and updated daily. Find more information about Crossref citation counts.The Altmetric Attention Score is a quantitative measure of the attention that a research article has received online. Clicking on the donut icon will load a page at altmetric.com with additional details about the score and the social media presence for the given article. Find more information on the Altmetric Attention Score and how the score is calculated. Share Add toView InAdd Full Text with ReferenceAdd Description ExportRISCitationCitation and abstractCitation and referencesMore Options Share onFacebookTwitterWechatLinked InReddit PDF (394 KB) Get e-Alerts Get e-Alerts