Concept:
According to the Bohr model, the electron in a hydrogen atom can occupy only certain discrete energy levels. The energy of the \(n^{th}\) orbit is given by
\[
E_n = -\frac{13.6}{n^2}\ \text{eV}
\]
where \(n = 1,2,3,\dots\) is the principal quantum number.
Step 1: Identify the ground state.}
The ground state corresponds to the lowest possible energy level, which occurs when
\[
n = 1
\]
Step 2: Substitute into the energy formula.}
\[
E_1 = -\frac{13.6}{1^2}
\]
\[
E_1 = -13.6\ \text{eV}
\]
Thus, the energy of the ground state of hydrogen is \(-13.6\ \text{eV}\).