Energy in the ground state of hydrogen atom is -13.6 eV. What is the energy in the first excited state ?

Explanation

To find the energy in the first excited state of a hydrogen atom, we can follow these steps:

### Step-by-Step Solution:

1. **Understand the Energy Formula**: The energy of an electron in the nth orbit of a hydrogen atom is given by the formula:
\[ E_n = -\frac{13.6 \, \text{eV}}{n^2} \]
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