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How a Separating funnel is used to separate mixtures

Answer Text:
Separating funnel
separation.
- Is used from separating a mixture with two or more immiscible liquids.
- Such liquids do not mix but instead form layers based on their densities.
- The heaviest liquid layer is found at the bottom of the separating funnel; while the lightest liquid is found at the top of the separating funnel.
- The liquids are drained one after the other by opening and closing the tap of the separating funnel.
Example: Separation of oil from water
Apparatus:
Beakers, separating funnel, paraffin oil, distilled water, rubber stopper.
Apparatus.

Procedure.
- The tap of the separating funnel is closed.
- Equal volumes of water and paraffin are put in a separating funnel until it is half full.
- The mouth of the funnel is closed with a stopper and the mixture shaken.
- The mixture is allowed to stand until two distinct layers are formed.
- The stopper is removed and the tap opened to allow the bottom layer to drain into the beaker.
- The tap is closed after most of the bottom layer has drained off.
- The beaker is removed and the rest of the bottom layer is drained into a separate container and discarded; to ensure that no part of the top layer (paraffin) gets into the beaker containing the bottom (water) layer.
- The other (top) layer is then drained into another beaker.
Observations:
- After the mixture has settled oil and paraffin separate into two layers.
- The first beaker contains only water; while the second beaker contains only paraffin.
Conclusion.
- Paraffin and water are immiscible.
- The top layer contains water which is denser while the top layer contains oil (paraffin) which is lighter.
Practical application:
- Extraction of useful substances from complex mixtures.