Question

Statement 1: Chloropropane has higher boiling point than Chloroethane
Reason:
Statement 2: Haloalkanes are polar molecules.
(A) Statement 1 is true, Statement 2 is true; Statement 2 is the correct explanation for Statement 1.
(B) Statement 1 is true, Statement 2 is true; Statement 2 is not the correct explanation for Statement 1.
(C) Statement 1 is true, Statement 2 is false.
(D) Statement 1 is false, Statement 2 is true.

Answer 1

Boiling point of any compound is directly proportional to the molecular mass compound. As the molecular mass increases the boiling point also increases. In the above question we have to compare the boiling point on the basis of the molecular mass. And halogens are highly electronegative which make the compound polar.

Complete step by step answer
Boiling point mainly depends on the two points. First of all, on the molecular mass such as the molecular mass increases the boiling point also increases. Secondly, if they are isomers then it depends on the branching, such as lesser the branching and higher the surface will be its boiling point.
In the case of chloropropane and chloroethane, ethane has less number of carbon atoms than propane and hence the molecular mass of ethane is lower than propane.
So, the molecular mass of chloropropane is greater than the molecular mass of chloroethane. Hence, the boiling point of chloropropane is higher than the boiling point of chloroethane.
Hence, Statement 1 is true.
As we know that halogens are more electronegative than carbon. And the electron density in the carbon halogen bond is more towards halogen. It proves that haloalkanes are polar molecules.
Hence, Statement 2 is true.
But this polarity is not the reason for higher boiling point.
So, option B is correct.

Note
The boiling point of a liquid depends on the surrounding environmental pressure. A liquid in a partial vacuum has a lower boiling point than the liquid which is at atmospheric pressure. A liquid at high pressure has a higher boiling point than the liquid which is at atmospheric pressure.