Out of the following, which one is not a possible energy for a photon to be emitted by hydrogen atom according to Bohr's atomic model?

The energy of $n{t}^h$ orbit of hydrogen atom is given as

$E_n=\frac{-13.6}{n^2}eV$     

$\therefore E_1=-13.6 eV$

$$\begin{gathered} \Rightarrow E_2=-\frac{13.6}{2^2}=-3.4 eV \\ \Rightarrow E_3=-\frac{13.6}{3^2}=-1.5 eV \end{gathered}$$

$\Rightarrow E_4=-\frac{13.6}{4^2}=-0.85 eV$

$\therefore E_3-E_2=-1.5-\left(-3.4\right)=1.9 eV$

$E_4-E_3=-0.85-\left(-1.5\right)=0.65 eV$

${\mathrm{E}}_4-{\mathrm{E}}_1=-0.85+13.6=12.75 \mathrm{eV}$

hence, 11.1 eV energy of photon is not possible.