Theoretical organic chemistry / by Julius B. Cohen.

  • Cohen, Julius B. (Julius Berend), 1859-1935.
Date:
1928
Catalogue details

Licence: In copyright

Credit: Theoretical organic chemistry / by Julius B. Cohen. Source: Wellcome Collection.

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    TABLE I. A 7i-5°-85° B S5°-90° C 90°-95° D 95 °-ioo° E ioo°-io5° F io5°-iio° G xio°-ii5° Residue. 19 C.C. 53 c.c. 26 C.C. 15 C.C. 13 C.C. 17 c.c. 21 C.C. 33 c.c. In the second fractionation (Table II.) each of the first distillates is redistilled and collected within a narrower range of temperature. Thus, the first fraction (A) is distilled until the thermometer registers 790. Fraction B is then added, and the distillate divided into two fractions, 79°-8i° and 8i°-85°. Fraction C is added, and so forth. The new fractions, C' and E', are again fractionated. Ultimately, two fractions are obtained; B' consisting of nearly pure benzene, and F' of nearly pure toluene. TABLE II. A' below 79° B' 79°-8i° C' 8i°-85° D' 85°-io5° E' xo5°-io8° F' io8°-iio° Residue A . . . 5 c.c. Added B . — 42 C.C. (10 C.C.*) „ c . — — (9 C.C.*) „ D,E — — —■ 50 C.C. „ F • — — — •—- (II C.C.*) ,, G . — — — — — 22 C.C. 42 C.C. * Refraction- ated C' — 12 C.C. 7 c.c. * Refraction- ated E' . —■ — — — 6 c.c. 5 c.c. 5 c.c. 54c.c. 7 c.c. 50 c.c. 6 c.c. 27 C.C. 42 c.c. Expt. 2.—Distil a mixture of 20 c.c. of alcohol, b.p. 78°, and 50 c.c. of water, b.p. ioo°. The mixture will not inflame. Collect the first 10 c.c. of the distillate. The liquid now contains such a large pro¬ portion of alcohol that it readily takes fire. If the fractional distillation has to be conducted in vacuo it is undesirable to interrupt the boiling in order to remove the receivers containing different fiactions. Various forms of apparatus have