Question

You can separate a mixture of sand, salt and water by:
A. filtration and distillation.
B. decantation and evaporation.
C. filtration and decantation.
D. decantation and crystallization.

Answer 1

Hint: We know mixing two or more substances together of different or same nature is called a mixture. Mixtures can be classified into separable and inseparable on the basis of separating all the components of mixtures into different substances original distinct substances.

Complete answer:
There are different ways in which one can separate various mixtures. In the question we are given with a mixture of sand, salt and water which can be separated in the following way.
Decantation is the process of separating a solid-liquid mixture, in such a mixture we can say that the solid particles out of the mixture get deposited at the bottom due to gravity and the liquid floats above it. Therefore it can be separated out by transferring the liquid floating above the sediments or solid particles of sand into another empty vessel and hence the solution of salt and water gets collected into the vessel and sand is separated out of the mixture.
This process is useful for only immiscible solutions or solid-liquid solutions. Now we are left with the solution of salt and water in the vessel which can be separated by the process of evaporation. Place the vessel in sunlight, on getting heated the water will turn into vapours and evaporate into the atmosphere. You will only be left with salt particles at the bottom of the vessel. Hence this is how once can separate such a mixture.

Therefore the correct option is B.

Note: Whenever one needs to separate out salt particles out of a solution evaporation is the best method. Two immiscible liquids of different densities can be separated using the above process of decantation.