The amount of energy released when an electron jumps from the seventh excited state to the first exc — Atomic Structure Chemistry Question

💡 Solution & Explanation

The seventh excited state is $n=8$ and the first excited state is $n=2$. For $\text{He}^+$ ($Z=2$), $\Delta E = 13.6 \times 2^2 \times (\frac{1}{2^2} - \frac{1}{8^2}) = 54.4 \times (\frac{1}{4} - \frac{1}{64}) = 54.4 \times \frac{15}{64} = 12.75$ eV. Therefore, correct answer is C.