Here are some physical properties that you can use to separate mixtures.
Solubility
Tea leaves do not dissolve in water, so you can use a strainer to filter them from your tea.
(from www.bellocq.com)
Particles of sand and mud are denser than water. They will settle out over time. The process is sedimentation.
Centrifugation speeds up the process of settling out . It works for both solids in liquids and liquids in liquids. In the lab, we use centrifugation to separate precipitates from a suspension.
Magnetism
Iron is magnetic. Steel isn't. You can use a magnet to separate iron filings from sulfur powder.
Vapour Pressure/Boiling Point
In distillation, a mixture of liquids is heated in a flask. The liquid with the lower boiling point boils first, and is condensed and collected. The liquid with the higher boiling point remains behind in the flask
Polarity
In chromatography, a mixture is dissolved in a liquid to make a solution. The solution is put on a solid material such as paper. The substances that are least attracted to the solid travel farthest along the paper. The separated substances form areas of colour.
Here is what different colours of ink look like in paper chromatography
(from fineartamerica.com)
Here is a summary of the different methods that are used to separate mixtures.
And here's a video that shows some of them in operation.
