The ionization energy for the hydrogen atom is `13.6 eV` then calculate the required energy in `eV` to excite it from the ground state to `1^(st)` excited state.

Explanation

Ionization energy `13.6 eV`
i.e. `1^(st)` energy state `-13.6 eV`
Energy of `1^(st)` excited state
i.e., `2^(nd)` orbit `=-3.4 eV`
so, `E_(2)-E_(1) = - 3.4 + 13.6 = 10.2 eV`