Question

A solvent (water) contains soluble and insoluble impurities. How will you separate them?
A. By filtration followed by evaporation
B. By sedimentation followed by precipitation
C. By crystallization
D. By fractional distillation

Answer 1

Hint: Separation of solid particles from liquid solutions can be made by sedimentation followed by decantation, filtration followed by evaporation, loading. Liquid mixtures can also be separated by different methods. Solid mixtures can be separated by handpicking, threshing, winnowing, magnetic separation.

Complete step by step solution:
Substances can be classified into two types-pure substances and mixtures. Pure substances consist of only one type of particle. Mixtures contain different types of particles. Mixtures can be of two types- homogeneous mixtures and heterogeneous mixtures. Homogeneous mixtures are the mixtures in which its constituents are uniformly distributed. Heterogeneous mixtures are the mixtures in which its constituents are not uniformly distributed. They can be differentiated from each other.
Fractional distillation is a process in which the separation is based on the boiling point. The chemical compounds are heated at a particular temperature in which one or more mixtures get vaporized. This is based on two liquid mixtures.
Filtration is a technique to separate solid particles which do not dissolve in liquid. It is a process of separating insoluble solids from a liquid through fine pores called filters. Evaporation is the process in which a liquid changes to a gaseous state of heating.
The solution we get after filtration also contains soluble impurities which may be separated by vaporizing.
During sedimentation, the solution may contain impurities after decantation which are not possible to separate.
Therefore option A is correct.

Additional information:
Sedimentation is a process in which solid particles are separated from a liquid solution. In this process, the solid particles settle down at the bottom of their own solution. To separate both, we have to pour the liquid into another container without disturbing the solid particles. This process is called decantation.

Note: Crystallization is a process in which a solid in its pure crystal form is separated from its saturated solution. A saturated solution is a solution in which no more solute is dissolved in the solution. It is different from filtration.