Q 12-12-012NEETJEE MainEasy
The total energy of the electron in the $n = 3$ orbit of hydrogen is
Answer: (A) $-1.51$ eV
Concept. Energy levels of hydrogen: $E_n = -\dfrac{13.6}{n^2}$ eV.
Step 1. Substitute $n = 3$.
$$E_3 = -\frac{13.6}{9} \approx -1.51\ \text{eV}$$
Answer. $-1.51$ eV (Option A).
Solution by Sreeraj P, M.Sc Physics