Assuming Bohr's atomic model for hydrogen-like ions, the ground-state radius of Li²⁺ is a₀/X, where a₀ is the first Bohr radius. The value of X is:
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Question

Assuming Bohr's atomic model for hydrogen-like ions, the ground-state radius of Li²⁺ is a₀/X, where a₀ is the first Bohr radius. The value of X is:

G1 Physics · Accepted Answer

For a hydrogen-like ion, the radius of the nth Bohr orbit is rₙ = a₀n²/Z. For Li²⁺, Z = 3, and for the ground state, n = 1. Therefore, r₁ = a₀(1)²/3 = a₀/3. Comparing with a₀/X gives X = 3. Correct option: A.