Determine the amount of (C9H13N)2·H2SO4 dissolved by employing the following method.

Finely powder a number of Tablets, equivalent to about 300 mg of dextroamphetamine sulfate, mix the powder in a mortar with 5 g of chromatographic siliceous earth, add 1 mL of methanol and 0.5 mL of ammonium hydroxide, and triturate to a uniform mixture. Transfer the mixture without delay to the chromatographic tube, and tamp as before. Wipe the mortar and pestle with a small amount of glass wool, and insert it into the tube on top of the column. Arrange a 125-mL separator containing 35 mL of 0.1 N sulfuric acid to receive the effluent. Pass 60 mL of chloroform through the column. Shake the separator vigorously for 1 minute, allow the layers to separate, and discard the chloroform. Add to the aqueous phase in the separator 2.5 g of sodium bicarbonate, preventing it from coming in contact with the mouth of the separator, swirl until most of the bicarbonate has dissolved. By means of a 1-mL syringe, rapidly inject 1.0 mL of acetic anhydride directly into the contents of the separator. Immediately insert the stopper in the separator, and shake vigorously until the evolution of carbon dioxide has ceased, releasing the pressure as necessary through the stopcock. Allow to stand for 5 minutes, and extract the solution with 50 mL of chloroform, shaking vigorously for 1 minute. Filter the chloroform extract through a pledget of filter cotton into a 100-mL beaker, rinse the cotton with a small amount of chloroform, and evaporate on a steam bath in a current of air or nitrogen to dryness. Heat and triturate the residue until the odor of chloroform is no longer perceptible. Allow the residue to cool, inducing it to crystallize. Reduce the crystals to a fine powder, heat at 80 for 30 minutes, and cool: the specific rotation of the acetylamphetamine so obtained, determined in a solution in chloroform containing 20 mg per mL, a 200-mm semimicro polarimeter tube being used, is between 37.5 and 44.0.

50C(rU / rS)