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Separatory Funnels

The separatory funnel is used primarily in extraction procedures. The sloping sides are designed to make it easy to distinguish layers. The stopcock-controlled outlet on the bottom is designed to allow the liquid to be drained out of the funnel. On top is a standard taper joint in which fits either a ground glass or Teflon stopper.

Separatory Funnels

The organic chem teaching labs have acquired several different types of sep funnels over the past years, with different types of stopcocks and stoppers. The Teflon stopcocks work better than the ground glass stopcocks; if you have a sep funnel with a ground glass stopcock, you may exchange for a Teflon style.

Different Types of Separatory Funnels

There are two different styles of stopper, too: plastic and ground glass. The disadvantage of the ground glass is that it can lodge permanently in the sep funnel if it is not removed and stored separately after use. Whichever style you have, make sure that the stopper fits snugly in the top of the funnel.

Separatory Funnel Caps

The Teflon-style stopcocks will leak unless they are properly assembled. The proper way to put them together is shown here. Note the small black gasket - it is important for preventing leaks.

Separatory Funnel Stopcock Assembly

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