Water benzene

Figure 16 shows observed and calculated VLE and LLE for the system benzene-water-ethanol. In this unusually fortunate case, predictions based on the binary data alone (dashed line) are in good agreement with the experimental ternary data. Several factors contribute to this good agreement VLE data for the mis-... 

If two pure, immiscible liquids, such as benzene and water, are vigorously shaken together, they will form a dispersion, but it is doubtful that one phase or the other will be uniquely continuous or dispersed. On stopping the agitation, phase separation occurs so quickly that it is questionable whether the term emulsion really should be applied to the system. A surfactant component is generally needed to obtain a stable or reasonably stable emulsion. Thus, if a little soap is added to the benzene-water system, the result on shaking is a true emulsion that separates out only very slowly. Theories of... 

The oil droplets in a certain benzene-water emulsion are nearly uniform in size and show a diffusion coefficient of 3.75 x 10 cm /sec at 25°C. Estimate the number of benzene molecules in each droplet. 

The use of a ternary mixture in the drying of a liquid (ethyl alcohol) has been described in Section 1,5 the following is an example of its application to the drying of a solid. Laevulose (fructose) is dissolved in warm absolute ethyl alcohol, benzene is added, and the mixture is fractionated. A ternary mixture, alcohol-benzene-water, b.p. 64°, distils first, and then the binary mixture, benzene-alcohol, b.p. 68-3°. The residual, dry alcoholic solution is partially distilled and the concentrated solution is allowed to crystallise the anhydrous sugar separates. 

An azeotropic mixture con tains two or more substances that distill together at a con stant boiling point The benzene-water azeotrope contains 9% water and boils at 69 C... 

Nitrobenzoic acid [121-92-6] M 167.1, m 143-143.5 , pK 3.46. Crystd from benzene, water, EtOH (charcoal), glacial acetic acid or MeOH/water. Dried and stored in a vacuum desiccator. 

Grafting of methylmethacrylate onto cellulose using ceric ammonium nitrate (Ce ) as the initiator in a benzene-water system is also demonstrated. The grafting yield in a benzene-water system is much lower than in the case of the methanol-water system and decreases by increasing the ratio of benzene to water. This can be due to the lower polarity and wetting power of benzene, which leads to poor swelling of the cellulose. 

As an example consider the exchange reaction between benzyl iodide and free iodide ions, Eq. (3-43).6 Mixing ethanolic solutions of benzyl iodide and radio-labeled potassium iodide started the isotopic exchange. At different times, samples were withdrawn and added to a benzene-water mixture, causing separation into two layers. The aqueous layer contained the iodide ions, and the organic layer contained the benzyl iodide. The activity of 1311 was determined in each layer. 

The Gibbs equation allows the amount of surfactant adsorbed at the interface to be calculated from the interfacial tension values measured with different concentrations of surfactant, but at constant counterion concentration. The amount adsorbed can be converted to the area of a surfactant molecule. The co-areas at the air-water interface are in the range of 4.4-5.9 nm2/molecule [56,57]. A comparison of these values with those from molecular models indicates that all four surfactants are oriented normally to the interface with the carbon chain outstretched and closely packed. The co-areas at the oil-water interface are greater (heptane-water, 4.9-6.6 nm2/molecule benzene-water, 5.9-7.5 nm2/molecule). This relatively small increase of about 10% for the heptane-water and about 30% for the benzene-water interface means that the orientation at the oil-water interface is the same as at the air-water interface, but the a-sulfo fatty acid ester films are more expanded [56]. 

Supercomputers become more and more useful, and the Insights they can generate become more and more unique, as the complexity of the system modelled Is Increased. Thus Interfaclal phenomena are a very natural field for supercomputation. In addition to the examples In this volume It may be useful to mention the work of Llnse on liquid-liquid benzene-water interfaces, which he studied with 504 H2O molecules, 144 CgHg molecules, and 3700 Interaction sites. He generated over 50 million configurations In 56 hours on a Cray-lA, and he was able to quantitatively assess the sharpness of the Interfaclal density gradient, which Is very hard to probe experimentally. Similarly Spohr and Helnzlnger have studied orientational polarization of H2O molecules at a metallic Interface, which is also hard to probe experimentally. 

Using the coupled first-order Eqs. (9a) and (9b) to describe the problem of heating benzene water mixture from 70 to 200°F in a 1-in. tube with 40-psig... 

A triangular diagram shows the range of explosive mixtures in the hydrogen peroxide-benzene-water ternary system, and also includes data for various oxygenated water-soluble organic compounds. 

Acyclic ADC compounds, which are more correctly named as derivatives of diazene, are generally prepared from hydrazine derivatives. For example, diethyl azodicarboxylate (Chemical Abstracts name diethyl diazene-1,2-dicarboxylate)5 is prepared from hydrazine by treatment with ethyl chloro-formate followed by oxidation with chlorine in benzene-water.6 Other oxidants which have been used include JV-bromosuccinimide,7 nitric acid,8 inorganic nitrates,9 potassium dichromate,10 silver carbonate on celite,11 and phenyl iodosotrifluoroacetate.12 The hydrazine derivative may also be... 

To the Grignard solution, 75 g. (71.5 cc., 0.5 mole) of ethyl benzoate (Org. Syn. 10, 51) in 200 cc. of dry benzene (Note 2) is added at such a rate that the mixture refluxes gently. The flask is cooled in a pan of cold water during the addition, which requires about an hour. After the addition is complete, the mixture is refluxed for an hour on a steam bath. The reaction mixture is cooled in an ice-salt bath and then poured slowly, with constant stirring, into a mixture of 1.5 kg. of cracked ice and 50 cc. of concentrated sulfuric acid. The mixture is stirred at intervals until all the solid which separates at the benzene-water interface has dissolved. If necessary, 50 g. of ammonium chloride is added to facilitate the decomposition of the magnesium salt, and additional benzene may be added if the amount present... 

Chen, H., Wagner, J. (1994a) An apparatus and procedure for measuring mutual solubihties of hydrocarbons + water Benzene + water from 303 to 373 K. J. Chem. Eng. Data 39, 470 -74. 

Udovenko, V.V., Aleksandrova, L.P. (1963) The vapor pressure of three components systems. IV. Formic acid-benzene-water. Zh. Fiz. Khim. 37, 52-56. 

Fig. 11 AFM image of a 260 nm thick film of PS-PEO cast from benzene in a benzene/ water atmosphere for 48 h. Reproduced from [44]...

Karasek et al. [1] determined hydrocarbons in benzene water extracts (pH7) of soil and in incinerator or fly ash by a variety of techniques including gas chromatography with flame ionization, electron capture and mass spectrometric detectors. Benzene water extractants were adjusted to pH4, 7 and 10 before the extraction in order to selectively extract various types of acidic and basic organic compounds in addition to hydrocarbons. 

The benzene-water extraction gas chromatographic procedure described in section 2.1.1.1 for the determination of aliphatic hydrocarbons in soil has also been applied to the determination of polychlorinated dibenzo-p-dioxins in soil [73],... 

Herriott and Picker (1975) have studied the reaction between sodium thiophenoxide and 1-bromobutane in benzene-water catalysed by various quaternary ammonium salts and by the dicyclohexyl-18-crown-6 isomers ([20] + [21]). The catalytic activities, as judged from the second-order rate constants, span a range of 104. The best catalyst appeared to be dicyclohexyl- 18-crown-6, directly followed by tetrabutylphosphonium chloride and tetrabutylammonium iodide. 

Other Hydrocarbon - Water Systems. Interaction parameters were generated for the benzene - water system. The data used were those of Scheffer (31 ) > Rebert and Kay 35) > and Connolly... 

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