Hindered Rotation of the Methyl Groups in Propane. The Heat Capacity, Vapor Pressure, Heats of Fusion and Vaporization of Propane. Entropy and Density of the Gas

Kemp, J. D.; Egan, Clark J.

doi:10.1021/ja01274a001

Cited by 104 publications

(53 citation statements)

References 0 publications

Supporting

Mentioning

Contrasting

Order By: Relevance

“…Depending on temperature, the values calculated from the equations of state of Younglove and Ely [33] and Miyamoto and Watanabe [34] show deviations from our experimental results between 0.05% and >0.2%. Figure 2 presents a comparison between experimental results on the coexistence curve of propane (saturated-liquid densities, saturated-vapour densities, and vapour pressures) [39,41,[43][44][45][46][47][48][49][50][51][52][53][54][55][56][57] and values calculated from preliminary correlation equations of Bü cker and Wagner [26]. In comparison with other pure fluids, the previous data situation of propane with respect to the saturated-liquid densities was relatively good.…”

Section: Discussionmentioning

confidence: 90%

See 1 more Smart Citation

Measurement of the (p,ρ,T) relation of propane, propylene, n-butane, and isobutane in the temperature range from (95 to 340) K at pressures up to 12 MPa using an accurate two-sinker densimeter

Glos

Kleinrahm

Wagner

2004

The Journal of Chemical Thermodynamics

View full text Add to dashboard Cite

Section: Discussionmentioning

confidence: 90%

“…In the temperature range from about (180 to 260) K, accurate data were not previously available. In this region, the results of Kemp and Eagan [55] show deviations that exceed À0.2%. For T 6 140 K, the results of Carruth and Kobayashi [54] and Tickner and Lossing [53] agree with our results within the uncertainty of our data.…”

Section: Discussionmentioning

confidence: 91%

Measurement of the (p,ρ,T) relation of propane, propylene, n-butane, and isobutane in the temperature range from (95 to 340) K at pressures up to 12 MPa using an accurate two-sinker densimeter

Glos

Kleinrahm

Wagner

2004

The Journal of Chemical Thermodynamics

View full text Add to dashboard Cite

“…The melting point of propane is the lowest among n-alkanes (T m = 85.45 K) the melting entropy being DS f /R = = 4.96 [7]. According to heat capacity data [7], there are no phase transitions in the interval 13-85 K. The potential barrier for internal rotation (rotation of the methyl groups about the C 3 -axis) is 13.8 kJ/mole [8,9].…”

mentioning

confidence: 98%

“…According to heat capacity data [7], there are no phase transitions in the interval 13-85 K. The potential barrier for internal rotation (rotation of the methyl groups about the C 3 -axis) is 13.8 kJ/mole [8,9]. In more recent studies of the triple point of propane, two solid phases were detected, one stable, the other metastable [10].…”

mentioning

confidence: 99%

Isochoric thermal conductivity of solid n-alkanes: propane C3H8

Konstantinov

Revyakin

Sagan

2009

Low Temperature Physics

View full text Add to dashboard Cite

The isochoric thermal conductivity of solid propane C 3 H 8 has been investigated on three samples of different densities in the temperature interval from 50 K to the onset of melting. In all the cases the isochoric thermal conductivity exhibits dependences that are weaker than Lµ1/T. The results obtained are compared with those for other representatives of n-alkanes. The experimental data are discussed within a model in which the heat is transported by low-frequency phonons and by «diffusive» modes above the phonon mobility edge.PACS: 66.70.-f Nonelectronic thermal conduction and heat-pulse propagation in solids; thermal waves; 63.20. K-Phonon interactions.Keywords: isochoric thermal conductivity, phonons, diffusive modes, solid propane.Normal alkanes C n H 2n+2 form a class of substances taking an intermediate, transitional position between simple molecular solids and long-chain polymers which attracts considerable interest. The n-alkanes have a deceptively simple composition and a molecular packing in the solid state: the lamellae of molecules are aligned as chains parallel to one another and nearly perpendicular to the lamella plane. Yet, despite this seeming simplicity, they show an extraordinary variety of dynamical behavior both in the solid and liquid states. There is an intriguing «odd-even» effect alternating the orthorhombic versus triclinic unit cells between the adjacent members of the series as well as the presence or absence of premelting rotator phases. Glassy crystalline «rotator phases» with a hexagonal symmetry are found below the melting points of the odd-numbered n-alkanes starting with n = 9. The difference between the phase transition and melting points increases with the chain length. The hexagonal modifications are also observed for the even-numbered n-alkanes starting with n = 22 [1,2]. The nature of the molecular disorder in the «rotator phases» of n-alkanes is not fully clear. Besides the more or less hindered rotation of the molecules about the long axes other additional forms of disorder have been discussed [3]. The melting point alternation is another well-known phenomenon in n-alkanes; that is, the even-numbered members of series melt at a relatively higher temperature than the odd-numbered members [1].The short-chain (n < 6) n-alkanes are the least known members of the series. Previously, we studied the isochoric thermal conductivity of methane [4] and ethane [5]. Here we explore studies of the heat transfer in saturated hydrocarbons further. The isochoric thermal conductivity of solid propane C 3 H 8 was studied on samples of different densities in the temperature interval from 50 K to the onset of melting. Constant-volume investigations are possible for molecular solids having comparatively high compressibility coefficients. Using a high pressure cell, it is possible to grow samples of sufficient density which can be cooled then with practically invariable volume whereas the pressure in the cell decreases. As samples of moderate densities are cooled the pressure in the sell dro...

show abstract

“…The composition dependence of TK was estimated by using Eq. (1) and the parameter C which is determined from the composition dependence of Tg, S ~ at each composition is then evaluated by using Eqs (3), (8) and (10). Practically, this quantity can be evaluated as a minus value of residual configurational entropy at TK obtained by the regular solution model.…”

Section: Estimation Of Excess Configurational Entropymentioning

confidence: 99%

Thermal study of glass transitions in binary systems of simple hydrocarbons

Takeda

Yamamuro

Suga

1992

Journal of Thermal Analysis

View full text Add to dashboard Cite

Glass transition phenomena of four binary systems composed of simple hydrocarbons were studied by means of the differential thermal analysi s (DTA). For all the systems, a definite glass transition was observed and a monotonous relation between the glass transition temperature (Ts) and composition (x) was obtained. The composition dependence of T s was analyzed in terms of the entropy theory based on the regular solution model. The theoretical prediction could not reproduce our results other than (l-butene)x(1-pentene)~-x system. This disagreement is considered to be due to deviations of the present systems from the regular solution, and the accompanying excess configurational entropy S~ was estimated as a function of composition.Extraordinarily large values of S~ were obtained for (propene)x(propane)l-x and (propene)~(1 -pentene) 1-~ systems.

show abstract

Hindered Rotation of the Methyl Groups in Propane. The Heat Capacity, Vapor Pressure, Heats of Fusion and Vaporization of Propane. Entropy and Density of the Gas

Cited by 104 publications

References 0 publications

Measurement of the (p,ρ,T) relation of propane, propylene, n-butane, and isobutane in the temperature range from (95 to 340) K at pressures up to 12 MPa using an accurate two-sinker densimeter

Measurement of the (p,ρ,T) relation of propane, propylene, n-butane, and isobutane in the temperature range from (95 to 340) K at pressures up to 12 MPa using an accurate two-sinker densimeter

Isochoric thermal conductivity of solid n-alkanes: propane C3H8

Thermal study of glass transitions in binary systems of simple hydrocarbons

Contact Info

Product

Resources

About