Funnel, Buchner micro

Filter the cold acetone rapidly into a glass-stoppered test tube by means of suction through a 2- or 3-ml. micro Buchner funnel, fitted with a fritted-glass plate of medium porosity. Wash the tube and funnel with 3 ml. of cold acetone and combine it with the filtrate. 

Funnels. The glass Bunsen fuimel which is used with the semimicro technic is 50 mm in diameter with a stem 60 mm long. The Bunsen funnel is easily and economically converted to a Buchner funnel by using a 20 mm porcelain disc as shown in Figure 2(6). The micro Buchner funnel has a diameter of 42 mm at the top, 8.5 mm diameter of perforated area, and stem of about 50 mm in length. The porcelain perforated disc is 20 mfn in diameter, has beveled edges, and fits inside the funnel at a depth of 30 mm from the rim. 

The crude derivative is collected on qualitative filter paper cut to fit a micro (1 cm) Buchner funnel and washed with 2-3 ml of ice water. The compound is then transferred to a 30 ml beaker, dissolved in 10-12 ml of water by heating to incipient boiling, and the solution is decolorized with 30-35 mg of activated charcoal. The suspension is stirred briefly then filtered as before to remove the charcoal. The filtrate is transferred to a 30 ml beaker, which is placed in an ice bath and the solution is stirred... 

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