Why does oxygen have a slightly lower first ionization energy than nitrogen (1314 vs 1402 kJ/mol)?
Answer and explanation
Correct answer: C. Repulsion between paired electrons in the 2p orbital of oxygen facilitates removal
Nitrogen has a half-filled 2p subshell (2p3) where each electron occupies its own orbital. Oxygen (2p4) has one doubly occupied 2p orbital; the electrostatic repulsion between the two paired electrons makes removing one electron easier.
Practise more Atomic Structure and Periodic Properties.
Free questions with an explanation for every one, and full timed Medical University Entrance Examination (Bulgaria) mock tests.
More Atomic Structure and Periodic Properties questions
- Which set of quantum numbers describes an electron in a 3d subshell orbital?
- What is the ground-state electron configuration of the transition metal chromium (Z = 24)?
- What is the ground-state electron configuration of the neutral copper atom (Z = 29)?
- Which rule states that electrons fill degenerate orbitals singly with parallel spins before pairing up?
- Why does boron have a lower first ionization energy than beryllium (801 vs 899 kJ/mol)?
- Which series lists the isoelectronic ions in order of decreasing ionic radius: N3-, O2-, F-, Na+, Mg2+, Al3+?