Atomic Structure: Practice Problem & Solution

Solution Explained:

To solve this problem, we apply the core principles of Atomic Structure. Understanding the underlying formula is key to arriving at the correct answer below:

Excitation energy is the energy required to excite the electron from the ground state ($n=1$) to a particular state. The energy of the first excited state ($n=2$) is $-13.6/4 = -3.4 eV$. The excitation energy is $-3.4 - (-13.6) = 10.2 eV$.