Question

Does light from a neon sign have a continuous spectrum? Explain.
Yes. Excited neon atoms emit photons of specific, discrete energies; however, there are an infinite number of possible transitions between energy states for neon. Because all of these transitions emit photons in the visible spectrum, these create a practically continuous spectrum, not a line spectrum.
Yes. Neon atoms do not form diatomic molecules, like hydrogen can. Only diatomic molecules like H emit line spectra; neon atoms emit continuous spectra.
No. Excited neon atoms emit photons of specific, discrete energies when the atoms transition from high energy states to lower energy states. These create a line spectrum, not a continuous spectrum.
No. Neon signs emit a nearly continuous spectrum, but they emit no photons at the specific, discrete energies when the atoms transition from low energy states to higher energy states.

Answer 1

Yes. When neon atoms are excited and emit light, they do so through a process called spontaneous emission. This means that the photons emitted can have a range of energies corresponding to the various possible transitions between energy states of the neon atoms. As a result, the light from a neon sign has a continuous spectrum rather than a discrete line spectrum.