Chem lab, help!?

Question

Hi, I did a lab called "spectroscopy-secrets of light". Please help me with this question:

1.) What causes the single elements in the gas phase to produce different colors in a line spectrum?

Thank you!

Answer 1

The excitation energy, whether it is a flame, electric arc, or electric spark causes electrons to be blasted off of the metal atom or ion. The electrons return, descending through the different energy levels of the atom until they all reach a ground state. Because the energy levels are quantized (specific), the electrons give off energy of particular wavelengths as they descend from one to the other. In spectroscopy, a prism separates all of the wavelengths of light. Because "all" of the wavelengths are not there, just the specific ones, they appear as lines on the spectrum rather than a wide colored smear. The single elements produce lines of specific colors (wavelengths) because the energy levels of each atom are different.