Some hydrogen-like atoms in ground state absorbs 'n' photons having same energy and on de-excitement — Atomic Structure Chemistry Question

💡 Solution & Explanation

Absorbing 'n' photons and emitting 'n' photons implies a single transition up and single transition down per atom, meaning excitation strictly to $n=2$. Excitation energy $\Delta E = 13.6 Z^2 (1 - \frac{1}{4}) = 10.2 Z^2$. For $Z=2$, $\Delta E = 40.8$ eV. For $Z=3$, $\Delta E = 91.8$ eV. Therefore, correct answer is A, B.