Bohr's first orbit radius for hydrogen:
A1 m
B1 cm
C10⁻¹⁵ m
D0.529 Å (= 5.29 × 10⁻¹¹ m, Bohr radius)
Answer & Solution
Correct answer: D. 0.529 Å (= 5.29 × 10⁻¹¹ m, Bohr radius)
a₀ = 0.529 Å (Bohr radius). For Z hydrogen-like ion in n-th orbit: r_n = n² a₀/Z. So radii grow with n².
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