The radius of the fifth orbit of Li²⁺ is ______ × 10⁻¹² m. Take radius of hydrogen atom = 0.51 Å.

Question

G1 Physics · Accepted Answer

For a hydrogen-like ion, rₙ = a₀ n²/Z For Li²⁺: Z = 3 n = 5 a₀ = 0.51 Å = 0.51×10⁻¹⁰ m Therefore, r₅ = (0.51×10⁻¹⁰)(25/3) = 4.25×10⁻¹⁰ m = 425×10⁻¹² m Final value: 425