PREPARATIONS 199 anhydrous potassium carbonate. After the mixture has been allowed to stand for 20-30 minutes, filter at the pump, and wash the residual carbonate with a small quantity of dry benzene. The benzene has now to be distilled off at atmospheric pressure and the residual phenylhydrazine at reduced pressure. For this purpose, fit a small dropping-funnel to the main neck of a 6o ml. Claisen flask, cork the other neck, and fit a water-condenser to the side-arm. Run about 30 ml. of the benzene solution into the flask, and heat the latter in an oil-bath, controlling the tempera-ture of the bath so that the benzene distils gently over. Allow the remainder of the solution to run in from the dropping-funnel as fast as the benzene itself distils over. When the benzene has been almost entirely removed, fit a capillary tube and a thermometer into the necks of the flask, and then assemble the complete apparatus for vacuum distillation, using either the simple apparatus shown in Fig. IZ(A) (p. 29) or a water-condenser fitted
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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.