engineering physics MCQ #442

The ionization energy of Li++ is 122.4 eV. What is the ionization energy of He+?

engineering physics MCQ #442

  1. Question 1

    Q1. The ionization energy of Li++ is 122.4 eV. What is the ionization energy of He+?

    • A) 54.4 eV
    • B) 122.4 eV
    • C) 13.6 eV
    • D) 27.2 eV

    Answer: 54.4 eV

    Explanation: Ionization energy is proportional to Z². For Li++, Z = 3, and for He+, Z = 2, so the ratio of ionization energies is (2/3)² = 4/9, hence 122.4 * 4 / 9 = 54.4 eV.