Chemistry - PERIODIC TABLE Question with Solution | TestHub

The first ionization energy (IE₁) of a molecule is generally higher than that of its constituent atom if the molecule has a stable electronic configuration or stronger bonding.

For N₂, the IE₁ is 1503 kJ/mol, while for atomic N, it is 1402 kJ/mol. This is because N₂ has a very stable triple bond, requiring more energy to remove an electron.

For O₂, IE₁ is 1164 kJ/mol, and for atomic O, it is 1314 kJ/mol.

For F₂, IE₁ is 1515 kJ/mol, and for atomic F, it is 1681 kJ/mol.

Thus, only N₂ has a higher IE₁ than its atom.