B Physical Constants

Physical Properties. Benzene, C H, toluene, C Hj-CH, and petrol (a mixture of aliphatic hydrocarbons, e.g., pentane, hexane, etc.) are colourless liquids, insoluble in and lighter than water. Benzene and toluene, which have similar odours, are not readily distinguishable chemically, and their physical constants should therefore be carefully noted benzene, m.p. 5 (solidifies when a few ml. in a dry test-tube are chilled in ice-water), b.p. 8i toluene, m.p. —93°, b.p. 110°. Petroleum has a characteristic odour. 

Chapter XI is devoted to Qualitative Organic Analysis. The subject b discussed in moderate detail and this, coupled with the various Sections and Tables of Physical Constants of Organic Compounds and their Derivatives in Chapters III and IV, will provide a satisfactory course of study in this important branch of chemistry. No attempt has been made to deal with Quantitative Organic Analysb in this volume. 

A forerun of approximately 180 mg. is collected below 110° (18 mm.). The infrared spectrum of this material is practically identical with that of the main distillate. Reported physical constants for 5,6-dihydro-2/f-pyran 2-one are b.p. 110° (15 mm.) and nf 1.4730.3... 

It is now necessary to find out whether the model shows interesting behaviour for certain values of a, b and N which are consistent with the facts of organic chemistry. Interesting behaviour means a jump from disorder to an ordered state. This can occur only in a narrow range of a, b and N and is independent of chemical and physical constants. Thus, the model makes statements about the matter which could have composed the first living system. The favoured ranges for interesting behaviour are ... 

Webster, G.R.B., Friesen, K.J., Sarna, L.P., Muir, D.C.G. (1985) Environmental fate modelling of chlorodioxins Determination of physical constants. Chemosphere 14, 609-622. 

Atlas of Spectral Data and Physical Constants for Organic Compounds, J.G. Grasselli, Ed., CRC Press, Cleveland, OH, B-189 (1974). 

P. J. Mohr, B. N. Taylor. CODATA Recommended Values of the Fundamental Physical Constants 2002. Rev. Mod. Phys. 2005, 77, 1-107. See also physics.nist.gov/constants (November 2006). 

Skinner B. J. (1966). Thermal expansion. In Handbook of Physical Constants, S. P. Clark Jr., ed. Memoir 97, The Geological Society of America. 

Small samples may readily be distilled with little decomposition, while large samples decompose significantly during (list, nation. The undistilled material may be satisfactory for use in alkylation reactions without purification. The checkers have (bund that 200 g. quantities of the product can reprodticibly lie distilled at approximately 1 mm. The reported physical constants for benzyl chloromethyl ether are b.p. 96-98° (9.5 imn.)2, n n 1.5264-1.5292. i2... 

Henrion M, Fishoff B. 1986. Assessing uncertainty in physical constants. Am J Phys 54 791-797. 

J. Holubek and O. Strouf, Spectral Data and Physical Constants of Alkaloids. Publishing House of Czechoslovak Academy of Sciences, Prague, 1%5-1971. (a) Spectrum 24, (b) Spectrum 193, (c) Spectrum 32, (d) Spectrum 437, (e) Spectrum 409, (f) Spectrum 210, (g) Spectrum 704. 

With the exception of the polarizabilities, data are from J. A. Riddick and W. B. Bunger, Organic Solvents, 3rd ed., Vol. II of A. Weissberger, Ed., Techniques of Chemistry, Wiley-Interscience, New York, 1970. Other physical constants may also be found in this source. 

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