An electron is revolving round the nucleus of He^+ ion with speed 2.188 * 10^6 m/s. The potential en — Atomic Structure Chemistry Question

💡 Solution & Explanation

Speed in a Bohr orbit is v = 2.188 * 10^6 * Z / n m/s. For He^+ (Z = 2), a speed of 2.188 * 10^6 m/s implies Z / n = 1 => n = Z = 2. In the n = 2 state of He^+, total energy is E = -13.6 * Z^2 / n^2 = -13.6 * 4 / 4 = -13.6 eV. Thus, the potential energy is P.E. = 2 * E = -27.2 eV.