Question

Which factor is most responsible for the increase in boiling points of noble gases from $\mathrm{He}$ to $\mathrm{Xe}$?

• A. Monoatomic nature
• B. Increase in polarisability
• C. Decrease in polarisability
• D. Decrease in Ionisation energy

Answer 1

The correct option is B

Increase in polarisability

Explanation for the correct option

1. As the size of the atom grows larger, the attracting force grows stronger.
2. As the force of attraction rises, the Polarizability will also rise.
3. A rise in polarizability is by far the most important component in the conversion of helium to xenon boiling temperatures.

Explanation for the incorrect options

Option A: Monoatomic nature

1. As the given statement of increase in boiling point involves hybridization, where size of cation increases.
2. Hence, the factor monoatomic nature is not the correct answer.As the given statement of increase in boiling point involves hybridization, where size of cation increases.

Option C: Decrease in polarisability

1. Increasing the boiling points of noble gases from $\mathrm{He}$ to $\mathrm{Xe}$ involves hybridization.
2. It gets increase in polarisability. So, the given statement is wrong.

Option D: Decrease in Ionisation energy

1. The prescribed statement, that the ionisation energy decreases, is an erroneous explanation of the process of increasing the boiling point and determining the atom's value.
2. So, Decrease in Ionisation energy is wrong.

Final answer: The factor that is most responsible for the increase in boiling points of noble gases from $\mathrm{He}$ to $\mathrm{Xe}$ is Increase in polarisability. The correct option is B.