Question

Gradual addition of electronic shell in the noble gases causes a decrease in their?

• A. Ionization energy
• B. Atomic radius
• C. Boiling point
• D. Density

Answer 1

The correct option is A Ionization energy

I.E will decrease as we move down because attraction falls off very rapidly with distance. An electron close to the nucleus will be much more strongly attracted than one further away. Atomic radius increase due to the addition of a new shell. B.P and density will increase as the molecular weight increases down the group.