MDCAT Chemistry MCQ #816

Why does the ionization energy of group 13 elements drop between Al and Ga?

MDCAT Chemistry MCQ #816

  1. Question 1

    Q1. Why does the ionization energy of group 13 elements drop between Al and Ga?

    • A) Poor shielding by d-electrons in Ga
    • B) Increased atomic radius
    • C) Lower effective nuclear charge
    • D) Greater electron-electron repulsion

    Answer: Poor shielding by d-electrons in Ga

    Explanation: Ga's d-orbital shielding is less effective than Al's, increasing IE. B and C contradict the trend.