MDCAT Chemistry MCQ #865

Why is the 3d orbital higher in energy than the 4s orbital during electron filling?

MDCAT Chemistry MCQ #865

  1. Question 1

    Q1. Why is the 3d orbital higher in energy than the 4s orbital during electron filling?

    • A) 4s has better penetration
    • B) 3d has higher angular momentum
    • C) 4s is closer to the nucleus
    • D) 3d is shielded differently

    Answer: 4s has better penetration

    Explanation: 4s orbital penetration allows it to fill before the higher-energy 3d orbital.