The energy of the nth orbit of the hydrogen atom is defined by the equation:\[E_n = - \frac{13.6}{n^2} \, \text{eV}\]For the second orbit, where \( n = 2 \):\[E_2 = - \frac{13.6}{2^2} = - \frac{13.6}{4} = - 3.4 \, \text{eV}\]The energy for the second orbit is therefore \( - 3.4 \, \text{eV} \).