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An electron in a hydrogen atom is found in an excited state with energy equal to -3.4 eV. What is its angular momentum?
- 3.72 × 10⁻³⁴ Js
- 2.10 × 10⁻³⁴ Js
- 1.51 × 10⁻³⁴ Js
- 4.20 × 10⁻³⁴ Js
Correct answer: 2.10 × 10⁻³⁴ Js
Solution
E = -13.6/n^2 = -3.4 eV gives n = 2. Angular momentum L = n*hbar = 2 * 1.055 x 10^-34 = 2.11 x 10^-34 Js.
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