Final answer:
When the hydrogen atom is in its second excited state, there are two maximum spectral lines observed.
Step-by-step explanation:
In the hydrogen atom, when the electron is in the second excited state (n = 3), there are multiple possible transitions to the second energy level (n = 2).
Each transition corresponds to the emission of a photon with a specific wavelength. For the second excited state, there are two possible transitions: n = 3 to n = 2 and n = 4 to n = 2. This means that there are two maximum spectral lines observed when the hydrogen atom is in its second excited state.