Engineering Board Exam Reviewer · Physics · hard
In the Bohr model of hydrogen (En = -13.6/n2 eV), how much energy is emitted when an electron drops from n = 2 to n = 1?
- 13.6 eV
- 3.4 eV
- 6.8 eV
- 10.2 eV
Answer
D. 10.2 eV
Solution
E = E2 - E1 = -3.4 - (-13.6) = 10.2 eV (Lyman-α, 122 nm).
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