Thermodynamic Properties of Toluene

Temperature Pressure Density Volume Int. energy Enthalpy Entropy C CT Sound speed Joule-Thomson 

The values in these tables were generated from the NIST REFPROP software (Lemmon, E. W., McLinden, M. O., and Huber, M. L., NIST Standard Reference Database 23 Reference Fluid Thermodynamic and Transport Properties—REFPROP, National Institute of Standards and Technology, Standard Reference Data Program, Gaithersburg, Md., 2002, Version 7.1). The primary source for the thermodynamic properties is Lemmon, E. W., and Span, R., Short Fundamental Equations of State for 20 Industrial Fluids, J. Chem. Eng. Data 51(3) 785-850, 2006. Validated equations for the viscosity and thermal conductivity are not currently available for this fluid 

The uncertainties in density in the equation of state are 0.05% in the liquid phase up to 540 K, 0.5% up to the critical temperature, 1% at higher temperatures, 0.5% at pressures from 100 to 500 MPa, and 0.2% in the vapor phase. The uncertainty for the saturated-liquid density (and densities near atmospheric pressure) approaches 0.01% around 300 K. The uncertainties in vapor pressure are 0.3% from 270 to 305 K, 0.05% from 305 to 425 K, 0.1% up to 555 K, and 0.15% up to the critical temperature. The uncertainty in heat capacities is 0.5% and rises to 3% in the critical region. The uncertainty in the speed of sound is 1% up to 500 K and 100 MPa and rises to 2% at higher pressures and higher temperatures. 

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Statistical Methods for Calculating Thermodynamic Functions Cable 5 Calculated and observed thermodynamic properties of toluene... 

The physical properties of toluene have been well studied experimentally. Several physical properties are presented in Table 1 (1). Thermodynamic and transport properties can also be obtained, from other sources (2—7). The vapor pressure of toluene can be calculated as follows (8), where P is in kPa and T... 

Gaw, W. J. S win ton, F. L. Thermodynamic properties of binary systems containing hexafluorobenzene. Part 4. Excess Gibbs free energies of the three systems hexafluorobenzene -l- benzene, toluene, and p-xylene Trans. Faraday Soc. 1968,64,2023-2034... 

Nissema, A. Karvo, M. Thermodynamic properties of binary and ternary systems. Part V. Vapour pressures and thermodynamic excess functions of toluene + dimethyl sulphoxide mixtures Finn. Chem. Lett. 1977, (8), 222-226... 

Karvo, M. Thermodynamic properties of binary and ternary mixtures containing sulfolane. VI. Vapour-hquid equihbtia for (benzene + sulfolane) and (toluene + sulfolane) J. Chem. Thermodyn. 1980,12, 1175-1181... 

Fernandez, J. Garriga, R. Velasco, I. Otin, S. Thermodynamic properties of binary mixtures containing n-alkylamines I. Isothermal vapour-liquid equilibrium and excess molar enthalpy of n-aliylamine + toluene mixtures. Measurement and analysis in terms of group contributions Fluid Phase Equilib. 1998,152, 243-254... 

The two monomers of major interest, styrene and ethylene, are well known and details can be found on all aspects of their technology elsewhere. Poly(ethylene-co-styrene) is primarily produced via solution polymerization techniques using metallocene catalyst/co-catalyst systems, analogous to the production of copolymers of ethylene with a-olefin monomers. Solvents that can be employed include ethyl-benzene, toluene, cyclohexane, and mixed alkanes (such as ISO PAR E, available from Exxon). The thermodynamic properties of poly(ethylene-co-styrene), including solvent interactions and solubility parameter assessments, are important factors in relation to polymer manufacture and processing, and have been reported by Hamedi and co-workers (41). 

Thermodynamic contributions from the internal rotation of several symmetric tops may be readily calculated by appropriate summation of terms in Table 4. Few reliable calculations, however, have been reported. Thermodynamic properties of propane and several methyl-substituted benzenes have been reported, for example, but subsequent more accurate work has shown the necessity for considering that the internal rotation may be restricted. " Although the subsequent calculations for m-xylene and p-xylene used 6-fold internal rotation barriers of 2.1 to 3.1 kJ mol", more recent statistical calculations for toluene employing the presence of free rotation suggest that internal rotation in the two xylenes may be effectively unrestricted. 

Murakami, S. Lam, V. T. Benson, G. C. The thermodynamic properties of binary aromatic systems. II. Excess enthalpies and volumes of benzene -t toluene and toluene -H isomeric xylene mixtures at 25.deg.C J. Chem. Thermodyn. 1969,1,397 7... 

Kokkonen, R Arvola, H. Thermodynamic properties of binary and ternary systems. Vapour-liquid equilibrium data in the triethylamine + toluene system. Thermochim. Acta 1984, 77, 333-339. 

For the non-oxidative activation of light alkanes, the direct alkylation of toluene with ethane was chosen as an industrially relevant model reaction. The catalytic performance of ZSM-5 zeolites, which are good catalysts for this model reaction, was compared to the one of zeolite MCM-22, which is used in industry for the alkylation of aromatics with alkenes in the liquid phase. The catalytic experiments were carried out in a fixed-bed reactor and in a batch reactor. The results show that the shape-selective properties of zeolite ZSM-5 are more appropriate to favor the dehydroalkylation reaction, whereas on zeolite MCM-22 with its large cavities in the pore system and half-cavities on the external surface the thermodynamically favored side reaction with its large transition state, the disproportionation of toluene, prevails. 

Since the solvent properties of dimethyl sulfoxide are widely different from those of hydrocarbons and halogenated hydrocarbons, it may be difficult to compare the kinetic and thermodynamic data for the C02H group (Table 16) directly with others. However, heating the carboxylic acid (68, X = OH) in toluene affords the sp isomer almost exclusively. Probably, the observed results with the carboxylic acid derive from difficulty in the formation of a hydrogen bond owing to a steric effect, in addition to the nonplanar conformation of the carboxyl group relative to the naphthalene. 

In order to optimize the antitumoral properties of radicicol, particularly in vivo, the same group synthesized the analogous cycloproparadicicol, where the epoxide function is replaced by a cyclopropane [64]. Submitted to the conditions of the previous RCM reaction (CH2C12, 42°C, 19h), cydopropyl triene 94 leads to the expected macrolide 95 in only 16% yield, along with 30% of the corresponding 28-membered dimeric macrocycle (Scheme 2.37). After numerous assays, the best conditions tested (toluene, 110 °C, 10 min) brought the yield up to 55%. In this case, the balance between thermodynamic and kinetic factors seems decisive for the course of the reaction. The fact that the monomeric product is predominant at elevated temperature indicates that this form is entropically favored. 

Several choices are available in defining the standard state of the solute. If the solute is a liquid which is miscible with the solvent (as, for example, in a benzene-toluene mixture), then the standard state is again the pure liquid. Several different standard states have been used for solutions of solutes of limited solubility. In developing a relationship between drug activity and thermodynamic activity, the pure substance has been used as the standard state. The activity of the dmg in solution was then taken to be the ratio of its concentration to its saturation solubility. The use of a pure substance as the standard state is of course of limited value since a different state is used for each compound. A more feasible approach is to use the infinitely dilute solution of the compound as the reference state. Since the activity equals the concentration in such solutions, however, it is not equal to unity as it should be for a standard state. This difficulty is overcome by defining the standard state as a hypothetical solution of unit concentration possessing, at the same time, the properties of an infinitely dilute solution. Some workers have chosen to... 

The nature of the lowest-lying excited states of the fullerenes has been difficult to identify with much certainty. From Shpol skii-type luminescence spectra recorded at 1.5 K it has been concluded that the first-excited singlet state in C70 is of A 2 character. The origins of the lowest energy transitions in Ceo, namely Si(T]g) and S2(Gg), have been assigned on the basis of fluorescence and excitation spectra, supported by theoretical calculations. " The luminescence properties and relaxation dynamics of single crystals of Qo have been described while related measurements have been made for solid films of Ceo " Similar studies have reported the luminescence spectral properties of 50 trapped inside the cavities of NiY zeolites. An analysis of the fine structure of electron-vibrational spectra has been made for 50 and its derivatives in a solid toluene matrix. The rate of triplet energy transfer between fullerenes in toluene solution has been measured as a function of temperature and used to derive thermodynamic parameters for the transfer process. ... 

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