An electron transitions from n=5 to n=2. Which series does this belong to, and what is the spectral region?
Q1. An electron transitions from n=5 to n=2. Which series does this belong to, and what is the spectral region?
Answer: Balmer, visible
Explanation: Balmer transitions end at n=2 and emit visible light. Lyman transitions end at n=1 (UV). The most tempting wrong option is A, which mixes transition levels with incorrect series.