Liquid benzene

Joe T and Albrecht A C 1993 Femtosecond time-resolved coherent anti-Stokes Raman spectroscopy of liquid benzene a Kubo relaxation function analysis J. Chem. Phys. 99 3244-51... 

It is possible (with lower initial Led temperature, higher initial loading, or higher regeneration temperature or pressure) for the transition paths to contact the saturated vapor curve in Fig. 16-22 rather than intersect beneath it. For this case, liquid benzene condenses in the Led, and the effluent vapor is saturated during part of regeneration [Friday and LeVan, AIChE]., 30, 679 (1984)]. 

Liquid benzene is chlorinated in the presence of metalhc iron turnings or Raschig rings at 40 to 60°C (104 to 140°F). Carbon tetrachloride is made from CS9 by bubbling chlorine into it in the presence of iron powder at 30°C (86°F). 

Irradiation of benzene and certain of its derivatives results in bond reorganization and formation of nonaromatic products. Irradiation of liquid benzene with light of 254-nm wavelength results in the accumulation of fulvene and a very small amount of tricy-clo[3.1.0.0 ]hex-3-ene, also known as benzvalene. The maximum conversion to this product in liquid benzene is about 0.05%. The key intermediate is believed to be a biradical formed by 1,3-bonding. 

Benzene An aromatic hydrocarbon which is a colorless, volatile, flammable liquid. Benzene is obtained chiefly from coal tar and is used as a solvent for resins and fats in dye manufacture. 

A reagent bottle containing 1 kg of benzene accidentally falls to tlic floor of a small enclosed storage area iiicasuring 10 m in vohnne. In time, the spilled liquid benzene completely evaporates. With this iiiformalion answer the following questions ... 

Follow the step-wise process outlined in Problem 31 to calculate the amount of heat involved in condensing 100.00 g of benzene gas (C6H6) at 80.00°C to liquid benzene at 25.00°C. Use Tables 8.1 and 8.2 for the specific heat, boiling point, and heat of vaporization of benzene. 

The heat of solution of iodine in benzene is +4.2 kcal/mole (heat is absorbed). Assuming the increase in randomness is the same when iodine dissolves in liquid benzene as it is in ethyl alcohol and in CC14, justify the prediction that the solubility of I2 in benzene is higher than in CC14 but lower than in alcohol. 

Completely Miscible Liquids (benzene and alcohol) show more complicated relations. The total pressure is usually intermediate between the pressures of the pure liquids, and in many cases less than the sum of these, but greater than that of the most volatile component (Regnault). 

In order to recover 80 per cent of the benzene, the humidity must be reduced to 20 per cent of the initial value. As the vapour will be in contact with liquid benzene, the nitrogen will be saturated with benzene vapour... 

A sample of hydrogen chloride gas, HC1, is being collected by bubbling it through liquid benzene into a graduated cylinder. Assume that the molecules pictured as spheres show a representative sample of the mixture of HC1 and benzene vapor ( represents an HCl molecule and O a benzene molecule), (a) Use the figure to determine the mole fractions of HCl and benzene vapor in the gas inside the container, (b) What are the partial pressures of HCl and benzene in the container when the total pressure inside the container is 0.80 atm ... 

FIGURE 5.19 As a result ot its open structure, ice is less dense than liquid water and floats in it (left). Solid benzene is denser than liquid benzene and "bpnzenebergs" sink in liquid benzene (right). 

Self-Test 7.17B Confirm that liquid benzene and benzene vapor are in equilibrium at the normal boiling point of benzene. 80.1°C, and 1 atm pressure. The enthalpy of vaporization of benzene at its boiling point is 30.8 kj-mol 1 and its entropy of vaporization is 87.2 J-K -mol. ... 

Explain why the standard molar entropy of liquid benzene is less than that of liquid cyclohexane. 

FIGURE 8.38 Some of the steps that represent fractional distillation of a mixture of two volatile liquids (benzene and toluene). The original mixture boils at A and its vapor has composition B. After condensation of the vapor, the resulting liquid boils at C and the vapor has composition D, and so on. 

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. 

Paje MLE, BA Neilan, I Couperwhite (1997) A Rhodococcus species that thrives on medium saturated with liquid benzene. Microbiology (UK) 143 2975-2981. 

Most liquids—benzene is a good example—behave predictably as the temperature changes. Benzene is a liquid between 5.5°C and 80.1°C, not too different from water, which freezes at 0°C and boils at 100°C. As liquid benzene cools, it becomes more dense. That is expected. As the thermal energy of the molecules decreases, they pack together more tightly. At the freezing point, solid benzene forms. The molecules assume the closest possible packing. This is why the solid phase of most compounds is denser than the liquid phase. 

From the three roots, only Z and Z2 are significant. The smallest root (Zj) relates to the liquid and the largest root (Zf) to the vapor. Thus, the density of liquid benzene is given by ... 

Figure 8-5. Comparison of EFP2 and experimental C—C RDFs for liquid benzene...

Jorgensen, W. L. Severance, D. L., Aromatic-aromatic interactions free energy profiles for the benzene dimer in water, chloroform and liquid benzene, J. Am, Chem. Soc. 1990, 112, 4768 1774. 

In practice these experiments are very difficult and expensive, and have typically been applied to systems such as liquid benzene (33). On the encouraging side, it should be noted that these techniques are indeed applicable to condensed-phase systems and are extremely informative concerning fundamental condensed-phase dynamics. 

A pipeline carrying benzene has developed a large leak. Fortunately, the leak occurred in a diked area and the liquid benzene is contained within the square 50 ft X 30 ft dike. The temperature is 80°F and the ambient pressure is 1 atm. It is a cloudy night with a 5 mph wind. All areas downwind with a concentration exceeding 4 times the PEL must... 

A storage vessel contains liquid benzene at 100°F. The vessel vapor space is inerted with pure nitrogen to a total pressure of 1/2-in of water gauge. Assume that the vapor space is saturated with benzene vapor. 

This is higher than the value given in Table 2.3 (i.e., 40.2 kJ/g) since we used benzene from Table 2.2 as a gas and here it was burned as a liquid. The difference in energy went into vaporizing the liquid benzene and was approximately 0.4 kJ/g. (See Table 6.1)... 

Worked Example 5.8 The two liquids benzene and bromobenzene are mixed intimately at 298 K. At equilibrium, the pressures of the gases above beakers of the pure liquids are 100.1 kPa and 60.4 kPa respectively. What is the vapour pressure above the mixture if 3 mol of benzene are mixed with 4 mol of bromobenzene ... 

From the top of the column, the propane that always accompanies the propylene feed emerges, talcing with it some of the benzene. In a flash tank, the propane is vented, and liquid benzene is recycled. From the bottom of the catalytic distillation column come the cumene, the PIPB, and some miscellaneous heavies chat are separated in a fractionator to make cumene, of 99.9% purity. The PIPB is separated in another column and fed to a second reactor with another zeolyte catalyst bed. In there the PIPB reacts catalyti-... 

SOLUBILITY MEASUREMENTS. The solubilities of the extracts were measured in liquid benzene. Approximately 100 mg of the extract was placed in a narrow tube. Excess benzene was added and the tube was shaken. After 24 hours, the tube was centrifuged and the supernatant was removed. Excess benzene was again added and the process was repeated. After 1 week, the insoluble portion was dried and weighed. The percent solubility is based on the weight of the insoluble extract that remained. 

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