The radius of the 2nd orbit of hydrogen atom is 2.12 Å. What is the radius of the 1st orbit?
Q1. The radius of the 2nd orbit of hydrogen atom is 2.12 Å. What is the radius of the 1st orbit?
Answer: 0.53 Å
Explanation: r2 = 4 * r1, r1 = r2 / 4 = 2.12 / 4 = 0.53 Å.