MDCAT Chemistry MCQ #818

Why is the atomic radius of gallium smaller than aluminum?

MDCAT Chemistry MCQ #818

  1. Question 1

    Q1. Why is the atomic radius of gallium smaller than aluminum?

    • A) Poor d-orbital shielding in gallium
    • B) Higher nuclear charge
    • C) Lower ionization energy
    • D) Greater electron affinity

    Answer: Poor d-orbital shielding in gallium

    Explanation: Gallium's d-electrons provide poor shielding, reducing atomic radius. B is a general trend, not the root cause.