Science - Earth Science
Standard 1 Objective 1
1 class periods of 70 minutes each
Students will analyze light given off by glowing elements using a spectroscope. They will relate the spectrum given off by a stationary source to one that is "red-shifted".
There are several ways to generate light for this experiment. The most difficult for the students is to burn small amounts of the various metal salts in a flame on a wire loop. The best way for students to see spectra is to buy the vapor tubes of each element or mixture of elements and the power source (a Tesla coil also works) that runs electricity through them. This is more expensive but they last a long time. You can also find commercially made light bulbs with mercury vapor, argon, and neon in them. If you have tubes with "air" in them, students could figure out what gases are in air. You would also need tubes of nitrogen, oxygen and carbon dioxide for them to look at.
Students should know that elements are pure substances with distinct properties. One of the properties is the banding pattern seen through a spectroscope when the substance is burned or heated. The radiation is given off in various wavelengths which can be viewed with a spectroscope or diffraction grating. If the object giving off the radiation was moving away from the viewer the lines will shift toward the red end of the spectrum.
Lesson Design by Jordan School District Teachers and Staff.