Question

What are polar and nonpolar solvents?

Answer 1

Hint: ‘Polar’ means having poles. Polar compounds have dipoles in them i.e. they have charge separation in them. The nonpolar ones are the opposite of the polar ones.

Complete answer:
Let us understand properly the concept of polar and non-polar solvents.
- We can say that a solvent is polar when there are dipole moments or a large number of partial charges. There will be an electronegative difference between the bonded atoms of the solvent.
- Non-polar solvents are those solvents which do not have partial charges or dipole moments in them. There will be very small or zero electronegativity difference between the bonded atoms of the solvent.
- Polar solvents can dissolve polar solutes since both the oppositely charged dipoles attract each other but they cannot dissolve non-polar solutes. Similarly, a nonpolar solvent can dissolve only nonpolar solutes and they cannot dissolve polar solvents.
- Water is a good example of a polar solvent. The hydrogen and oxygen present in water have large electronegativity differences between them and this makes it a polar solvent. The hydrogen atom acquires a partial positive charge while the oxygen atom acquires a partial negative charge and when a polar solvent is added to water both hydrogen and oxygen attracts the opposite partial charges of the solute.
- Some of the common examples of non-polar solvents are benzene, hexane, toluene, pentane etc.

Note:
Some of the organic compounds which have electronegative atoms like oxygen, nitrogen and fluorine can form a hydrogen bond with water which is a polar solvent, and they become highly soluble in it due to the hydrogen bond.