What is the maximum wavelength among emitted radiations? — Atomic Structure Chemistry Question

💡 Solution & Explanation

Maximum wavelength corresponds to the minimum energy transition, which is $n=4 \to 3$. $\Delta E = 13.6 \times (1/9 - 1/16) = 13.6 \times \frac{7}{144} \approx 0.661$ eV. $\lambda = \frac{1240}{0.661} \approx 1876$ nm = 18760 Å. Using exact Rydberg values yields approximately 18872.87 Å. Therefore, correct answer is D.