Question

Which method is commonly used to separate salt from water?
A) Sedimentation
B) Filtration
C) Evaporation
D) Condensation

Answer 1

Hint: We have to remember that the molecular formula of water is \[{{\text{H}}_{\text{2}}}{\text{O}}\]. The molecular weight of water is \[{\text{18g}}\]. The water has intermolecular hydrogen bonding between the water molecules. The water can exist in all the states of matter. A solid state of water is called an ice cube. The gas state of water is called water vapour. The liquid state of water is called such water.

Complete answer:
We must have to know that the sodium chloride is salt present in water. The boiling point of water is less than the boiling point of salt. The sodium chloride salt has an ionic bond between sodium ion and chlorine ion. But water molecules have only covalent bonds between hydrogen and oxygen atoms in the molecules and hydrogen bonds between other water molecules. Hence, the boiling point of salt is greater than water.
This is the basic concept for the separation of salt from water. Hence, evaporation is the best technique for separation of salt from water.
Sedimentation is used to separate the dust particles from water.
Filtration is used to separate the big particles from water.
Condensation is a technique to collect the purified water, but not the right way to separate salt from water.
Hence, from the above discussion
Option A is not correct, Sedimentation method is not commonly used to separate salt from water.
Option B is not correct, Filtration method is not commonly used to separate salt from water.
Option C is correct, Evaporation method is not commonly used to separate salt from water.
Option D is not correct, Condensation method is not commonly used to separate salt from water.

Note:
We must remember that water is classified as two types. This classification is based on the amounts of minerals. The two types of water are hard water and soft water. The hard water means water contains high amounts of minerals ions. The soft water means water contains low amounts of minerals ions. The hardness of water is divided into two types. There are temporary and permanent hardness of water. This classification of hardness is dependent on the salt contained in the water.