The radius of the innermost orbit of the hydrogen atom is :A5.3×10⁻¹¹ mB3.5×10⁻¹¹ mC5.3×10⁻¹² mD3.5×10⁻¹² mAnswer: A. 5.3×10⁻¹¹ m Read Explanation: The radius of the innermost electron orbit of a hydrogen atom is 5.3×10⁻¹¹ m.Read more in App