Atomic Emission Spectra

Spectrum tubes, fluorescent light bulbs, novelty “plasma globes,” and glowing “neon” signs all have one thing in common— they contain a gas that glows a specific color when a high voltage is applied to it. In this demonstration, this color will be viewed through a Flinn C-Spectra™. It is a holographic diffraction grating that separates, or diffracts, light in the same manner as a traditional ruled diffraction grating. It is ideal for the simple observation of spectral emission lines that make up the observed colors of the glowing gases. The advantage to the C-Spectra is that it can be held at any angle and the emission spectrum can still be easily observed. In Part B, an inexpensive “plasma globe” will be prepared from a Tesla coil and a simple light bulb.