The ratio of the radius of the second orbit of He+ to that of the third orbit of Be3+ is
Q1. The ratio of the radius of the second orbit of He+ to that of the third orbit of Be3+ is
Answer: 2/9
Explanation: Radius ∝ n²/Z; ratio = (2²/2)/(3²/4) = 2/9, applying the formula for radius of nth orbit in hydrogen-like atoms.