The ratio of energies of first excited state of ion and ground state of H-atom is — Atomic Structure Chemistry Question

💡 Solution & Explanation

First excited state of $\text{He}^+$ ($Z=2, n=2$): $E = -13.6 \frac{2^2}{2^2} = -13.6$ eV. Ground state of H-atom ($Z=1, n=1$): $E = -13.6 \frac{1^2}{1^2} = -13.6$ eV. The ratio is 1:1. Therefore, correct answer is A.