Funnel , addition stopper

Another method involves the use of a hopper for the solid (Fig. 5-18) which has a rubber stopper or a glass valve as a seal between the reaction flask and the funnel. Addition is effected by raising the rod attached to the stopper. If the solid clogs the neck of the flask, it may be dislodged by the part of the rod which passes through the stopper. 

SO that the ether drains as rapidly as possible into the flask. Close the stopcock. transfer the co/d ethereal solution of diethylamine to the funnel, and stopper the funnel. Some white smoke may form in the funnel during this transfer. Add the ethereal solution of diethylamine dropwise to the stirred solution of acid chloride over a period of about 10-15 min. While this solution is being added to the flask, quantities of white smoke will be produced. After the addition is complete, continue stirring for 15 min to ensure completion of the reaction. 

After 3 hours, replace the separating-funnel by a reflux condenser, and the thermometer by a stopper. Add 11 g. of zinc dust in small portions by rapid removal of the stopper at such a rate that the liquid is first brought to the boil (usually about 2 portions of 2 g. each) and is then maintained gently boiling. A ooid too rapid addition of the zinc, otherwise the reaction will become too vigorous, and rapid immersion of the flask in ice-water will be necessary to control the effervescence. 

Dissolve 9-5 g. of hydrazobenzene (Section IV,87) in the minimum volume of ether (about 90 ml. are usually required), and add this solution in small portions from a separatory funnel to 100 ml. of ice-cold dilute hydrochloric acid (1 1) contained in a 350 ml. conical flask stopper the flask and shake after each addition. Benzidine hydrochloride separates out during the reaction. After all the hydrazobenzene has been introduced, add 50 ml. of concentrated hydrochloric acid and allow the mixture to stand for 30 minutes in ice water. Filter the benzidine hydrochloride at the pump, wash it first with 20 ml. of dilute hydrochloric acid (1 1) and then with two or three 20 ml. portions of ether (to dissolve any unchanged hydrazobenzene) (1). 

In figure 4 is shown how a separatory funnel and a pressure equalized addition funnel are made. The funnel part is just a PP funnel from the grocery store and what it is attached to is a stainless steel ball valve. See how the addition funnel is made by using a rubber stopper and an extra extension of tubing to the top of the funnel Well, that s how one can make a sealed addition funnel out of the ordinary glass separatory funnel that one gets with a distillation kit or from wherever. 

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