Observing Gas Lamps

Caution:

1. Some power supplies for gas tubes have exposed metal contacts. Because the gas lamp is a high voltage light source, do not touch the metal contacts that connect the gas tube to the power supply.
2. Never look at the sun or a tanning lamp with a spectroscope. Eye damage may occur from brightness and from high energy ultraviolet photons.

Most high schools have gas lamps and power supplies. Try to observe at least three different types of gas lamps. Different kinds on gas lamps include: Hydrogen, Helium, Mercury, Nitrogen and Neon. If you are unable to locate a gas lamp to observe, email us and we will make other arrangements.

Draw the pattern of emitted light observed with the spectroscope for three gas lamps. Use the scales provided in Solids and Light Activity 2 (pages 2-3 and 2-4). You make like to use colored pencils or markers to indicate the position of color(s). Add a written description to record which colors seem bright.

In the table below record the color of light emitted by each gas lamp that is related to the greatest and least energy per photon.

Gas	Greatest Energy	Least Energy

How can you tell which particular color of light emitted by each gas lamp results in the greatest number of photons emitted?

In the table below record the color(s) of light for which the greatest numbers of photons are emitted by each gas lamp.

Gas	Greatest Number of Photons

What are the similarities and differences among the light patterns observed for the various gases?