The ionization energy of He^+ ion is x eV. The ionization energy of Be^3+ ion should be — Atomic Structure Chemistry Question

💡 Solution & Explanation

Ionization energy is directly ∝ Z^2. For He^+ (Z = 2), I.E. is ∝ 2^2 = 4, so I.E._He+ = 4 * I.E._H = x => I.E._H = x/4. For Be^3+ (Z = 4), I.E. is ∝ 4^2 = 16. Therefore, I.E._Be3+ = 16 * I.E._H = 16 * (x/4) = 4x eV (option a). Note: The printed answer key in the book incorrectly lists (b) 2x eV.