The ground-state binding energy of hydrogen is 13.6 eV. Find the energy required to remove the electron from the first excited state of Li²⁺.
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The ground-state binding energy of hydrogen is 13.6 eV. Find the energy required to remove the electron from the first excited state of Li²⁺.

G1 Physics · Accepted Answer

Li²⁺ is hydrogen-like with Z = 3. In the first excited state n = 2, the binding energy is 13.6 Z²/n² = 13.6 × 9/4 = 30.6 eV. This is the ionization energy from that state. Correct answer: A.