5.1: Separating Funnel
A separating funnel is used to separate immiscible liquids.
Liquids that do not mix with each other are said to be immiscible. Two immiscible liquids, such as oil and water, can be separated by using a separating funnel. the mixture is placed in a separating funnel and allowed to stand. The oil and water form two separate layers, with the less dense liquid being ontop. The stopper is removed and the tap opened. The bottom layer is run off and collected in a container placed under the tap. The top layer remains and can be collected in a separate container.
For oil and water, the lighter liquid (oil) collects above the heavier liquid (water). When the tap is opened, the water is run out and the tap is closed before the oil reaches the bottom. Seapration is never entirely complete.