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The radius of the second Bohr orbit for hydrogen atom is: (Planck's const. h = 6.6262 × 10⁻³⁴ Js; mass of electron = 9.1091 × 10⁻³¹ kg; charge of electron = 1.60210 × 10⁻¹⁹ C; permittivity of vacuum ε₀ = 8.854185 × 10⁻¹² kg⁻¹ m⁻³ A²)
- 1.65 Å
- 4.76 Å
- 0.529 Å
- 2.12 Å
Correct answer: 2.12 Å
Solution
The radius of the second Bohr orbit for a hydrogen atom is determined by the formula rₙ = n² * (ε₀ * h²) / (π * m * e²), where n is the principal quantum number. For n=2, this calculation results in a radius of approximately 2.12 Å, making option D the correct choice.
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