Xylenes physical constants

Colloidal potassium has recently been proved as a more active reducer than the metal that has been conventionally powdered by shaking it in hot octane (Luche et al. 1984, Chou and You 1987, Wang et al. 1994). To prepare colloidal potassium, a piece of this metal in dry toluene or xylene under an argon atmosphere is submitted to ultrasonic irradiation at ca. 10°C. A silvery blue color rapidly develops, and in a few minutes the metal disappears. A common cleaning bath (e.g., Sono-clean, 35 kHz) filled with water and crushed ice can be used. A very fine suspension of potassium is thus obtained, which settles very slowly on standing. The same method did not work in THF (Luche et al. 1984). Ultrasonic waves interact with the metal by their cavitational effects. These effects are closely related to the physical constants of the medium, such as vapor pressure, viscosity, and surface tension (Sehgal et al. 1982). All of these factors have to be taken into account when one chooses a metal to be ultrasonically dispersed in a given solvent. 

The engine characteristics of aromatic hydrocarbons seem strongly dependent upon the nature of the side chain. The alignment of the knock resistance of the polymethyl-benzenes with structure corresponds quite closely with that found to be characteristic of the physical constants. The vicinal derivatives o-xylene, hemimellitine, and prehnitene... 

Physical Constants of Hydrocarbons C,-C,o. STP 109A, ASTM. 1916 Race St., PMadelphia, PA 19103. The mixed xylene (p/m-xylene) density based upon a 1 3 ratio of p-xylene to m-xylene. C phis aromatics based upon the average relative density values of the 30 C -C,o aromatics. 

Recently, the kinetics of the ammoxidation of m-xylene (1) and xylene isomers (2) over vanadium catalyst, and of m-xylene over mixed vanadium catalysts (3) were reported. This paper summarizes the results concerning the specific rate constants for each reaction path obtained in the above studies and adds some data on physical properties of each catalyst. 

Characteristic Physical Property Constants 69 Figure 3.1 Structural formula of m-xylene. 

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