In a hydrogen atom transition from n=4 to n=2, the emitted photon belongs to:
ALyman
BPaschen
CPfund
DBalmer (visible: Hβ, 486 nm)
Answer & Solution
Correct answer: D. Balmer (visible: Hβ, 486 nm)
To n=2 → Balmer. n=4 to n=2: Hβ, blue-green visible at λ ≈ 486 nm. Energy = 13.6(1/4 - 1/16) = 2.55 eV.
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