For ¹H ground state to first excited state (n=2), photon required:
A27.2 eV
B3.4 eV
C13.6 eV
D10.2 eV (= 13.6 × (1 - 1/4) = 10.2)
Answer & Solution
Correct answer: D. 10.2 eV (= 13.6 × (1 - 1/4) = 10.2)
ΔE = E_2 - E_1 = -13.6/4 - (-13.6) = -3.4 + 13.6 = 10.2 eV. UV photon (λ ≈ 121.6 nm, Lyman α).
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