MDCAT Chemistry MCQ #791

A student observes that the ionization energy of oxygen is lower than that of nitrogen. Which factor primarily accounts for this anomaly?

MDCAT Chemistry MCQ #791

  1. Question 1

    Q1. A student observes that the ionization energy of oxygen is lower than that of nitrogen. Which factor primarily accounts for this anomaly?

    • A) Higher atomic radius in oxygen
    • B) Increased effective nuclear charge
    • C) Electron-electron repulsion in paired 2p electrons
    • D) Greater stability of half-filled subshells

    Answer: Electron-electron repulsion in paired 2p electrons

    Explanation: Oxygen's paired 2p electrons experience repulsion, lowering ionization energy. Option D refers to nitrogen's half-filled stability, not oxygen.