You are handed a mixture of sand and salt. How do you separate the two substances? Anything added to the mixture has to be retrieved. [5 MARKS]
Explanation: 1 Mark each
1. A mixture of sand and salt is taken in a beaker and water is added to it.
2. After a few seconds of stirring, since salt is soluble in water, the salt will dissolve into the water.
3. The sand being heavier settles at the bottom of the beaker by a process which is known as sedimentation.
4. The sand can be separated from the salt solution by decantation or filtration.
5. The remaining mixture of salt and water is heated and the water evaporates to form water vapour.
6. Now, only salt is left into the beaker and the water vapour can be converted back into water through condensation.