Further Exploration of Light Patterns

Spectra of Gases

To see the spectra of a large number of gases click here. Scroll down to about one-third of the page where you will find the spectra of several gasses. These photos were recorded with a spectroscope very similar to the one that you made. The numbers at the top of each spectrum are the energies of the photons in electron volts.; For simulations of the spectra of a large number of gases using the best available data click here. This page contains some very old programming which is no longer considered safe. So, if you click on individual elements, your computer will probably refuse to run the program However, it is safe to look at the pictures. At the top of the screen is a so-called continuous spectrum. This spectrum contains all energies of photons in the visible range. As you saw with your own spectroscope, this pattern of light is observed for the incandescent lamp.
: Skip the sum's spectrum for now; we will come back to it later. Look at the spectra for the various gases and answer the questions below. The pattern of light emitted by gas lamps is called a discrete spectrum.The general pattern is a set of bright lines of color in a dark background. The spectrum of the compact fluorescent lamp that you looked at with your spectroscope was similar to a discrete spectrum but somewhat more complex. It had some bright lines but also part of a continuous spectrum. We will discuss the details of why in a later activity.

Answer the questions below about the spectra that you have observed.