METHODS AND MANIPULATION 49 (or of a mixture of solvents) to cause each zone to pass down the tube and ultimately to emerge as a solution of the pure com-ponent. If the components are colourless, their separation can often be followed by working in a quartz (or special glass) tube which is placed in the light of a mercury lamp. The separate zones are then often revealed by their fluorescence. The process of chromatographic separation is illustrated in the following experiment, in which a wider tube than usual is employed to give a reasonably rapid separation within the time normally available to students. The alumina employed is the usual active alumina as supplied by dealers. Chromatographic Separation of a Mixture of o- and p-Nitroaniline. Prepare a glass tube A (Fig. 24) in which the wider portion has a diameter of 3 cm. and a length of ca. 30 cm.: the narrow portion at the base has a A diameter of 5-7 mm. Wash the tube thoroughly (if necessary, with chromic acid, followed by distilled
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This note was uploaded on 09/19/2011 for the course CHM 2211 taught by Professor Castalleano during the Fall '06 term at University of Florida.