Mercury-vapor lamps were developed in 1835 as a source of light and was discontinued in favor of metal-halide lamps. Shown below is the emission spectrum of a mercury-vapor lamp. Identify if this is a continuous or line emission spectrum.

Where does the Paschen series lie in the electromagnetic spectrum if its emission lines have n_f = 3?

Lyman was able to see emission lines with n_f = 1 in the ultraviolet region. Why are n_f =2 not observed?

Identify the transition with the least energy based on the given diagram

Determine which of the following produces a shorter wavelength based on the quantum model for the hydrogen atom.