Question

Which solvent is used for dry-cleaning of clothes?
(A) Carbon tetrachloride
(B) Alcohol
(C) Acetone
(D) Freon

Answer 1

Hint: Dry-cleaning means the cleaning of clothes without using water and just by using organic non-polar solvents. Solvent should be such that it evaporates easily and there is no need for heat to dry such solvents.

Step by step answer:
We know that carbon tetrachloride is made up of four chlorine atoms and one carbon atom. The carbon can bond four bond by \[{\rm{s}}{{\rm{p}}^{\rm{3}}}\] hybridization the bond is sigma bond and the molecule is similar to that of methane in which carbon attached to four hydrogen.
In Carbon tetrachloride, each chlorine atom has two electrons non bonded which makes net dipole charge zero, these will make it non-polar.
Alcohol is having oxygen and hydrogen which will bond with water and it is polar. The alcohol is solvent in which polar solute will dissolve. It cannot evaporate easily.
Acetone has a ketone group which will make it polar. It evaporates easily but can’t be used as a cleaning agent as it will not form bonds with nonpolar molecules like dirt and oil so cannot clean the oily clothes.
Freon is not at all used as a dry cleaning solvent as it damages the beads it corrodes the surface in which it comes in contact with. It is very harmful as it catches fire easily. It cannot be used in day to day life. There are various Freon’s known.

Hence, the correct answer is (A) Carbon tetrachloride.

Note: The most important thing is to know what is polar and non-polar solvent, as the polar solvent will form bonds with clothes and nonpolar will help to remove dirt as it forms the bond with sticky substances.