2. Separation by Centrifugation
If we have a mixture of fine suspended particles in a liquid,we can separate it by the process of filtration by using a filter paper.This process is,however,very slow.But we can separate the suspended particles of a substance in a liquid very rapidly by using the method of centrifugation.Centrifugation is done by using a machine called centrifuge. We can now say that: Centrifugation is a method for separating the suspended particles of a substance from a liquid in which the mixture is rotated (or spun) at a high speed in a centrifuge.
In the method of centrifugation, the mixture of fine suspended particles in a liquid is taken in a test-tube (called centrifuge tube). The test-tube is placed in a centrifuge machine and rotated rapidly for some time. As the mixture rotates round rapidly, a force acts on the heavier suspended particles in it and brings them down to the bottom of the test-tube. The clear liquid, being lighter, remains on top (see Figure 69). We can separate the clay particles suspended in water very rapidly by the method of centrifugation. The suspension of clay particles in water is taken in a test-tube and rotated very fast in a centrifuge machine.The clay particles settle down at the bottom of the test-tube and clear water remains at the top. They can now be separated by decantation.
Notes
Matter in Our Surroundings - Notes
1. 3. Non-Metals are Bad Conductors of Heat and Electricity.
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3. 7. Metals are Solids at the Room Temperature
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4. The Case of a Liquid Solute Dissolved in a Liquid Solvent
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6. 11. Metals Usually Have a Silver or Grey Colour
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7. 7. Non-Metals may be Solid, Liquid or Gases at the Room Temperature.
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12. 6. Non-Metals are Not Strong. They Have Low Tensile Strength.
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13. Separation Of Mixture Of a Solid And a Liquids
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14. To Study the Properties of a Colloid
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19. To Study the Properties of a Compound of Iron and Sulphur
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20. 1. Separation by a Suitable Solvent
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21. 11. Non-Metals Have Many Different Colours.
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25. 3. Metals are Good Conductors of Heat and Electricity.
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26. 6. Metals are Usually Strong. They Have High Tensile Strength.
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30. 2. Separation by a Separating Funnel
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31. To Distinguish a Colloid from a Solution
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35. Experiment to Obtain Coloured Component (Dye) From Ink
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38. To Study the Properties of a Solution
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40. 1. Separation by Fractional Distillation
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41. 1. Non-Metals are Not Malleable. Non-Metals are Brittle.
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43. To Separate the Salt-Water Mixture (or Salt-Solution)
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47. Chemical Formula for daily use material
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50. To Study the Properties of a Suspension
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