The lowest energy state that an electron can occupy is the ground state.
An electron is elevated to a higher energy level when it absorbs energy equal to the difference between the higher energy level and the lower energy level. This correlates to specific energy intervals as electrons cannot exist between energy levels.
When an excited electron relaxes back down to the ground state, it releases energy in the form of a photon of light equal to the energy difference between the higher and lower level.
In fluorescence, an electron is excited to a higher energy level by absorbing energy in the form of light. However, in chemiluminescence, an electron is excited to a higher energy level by absorbing energy that is released during a chemical reaction.
Luminol emits a blue/white glow when oxidized and reacts with the iron in hemoglobin. This enables forensic scientists to identify trace amounts of blood.
Source: Lara Al Hariri at the University of Massachusetts Amherst, MA, USA
Here, we show the laboratory preparation for 10 students working in pairs, with some excess. Please adjust quantities as needed.
1 Stirring hotplate |
1 Bunsen burner with tubing |
2 Lab stands |
3 Clamps |
1 Pair of flask tongs |
4 10-mL graduated cylinders |
1 50-mL graduated cylinder |
3 25-mL Erlenmeyer flasks |
1 250-mL filter flask |
1 50-mL beaker |
2 250-mL beakers |
1 400-mL beaker |
1 600-mL beaker |
2 25-mL test tubes |
2 Büchner funnels |
1 Long glass stirring rod |
1 Medium stir bar |
2 Thermometers |
2 Spatulas |
6 Boiling chips |
1 Medium filter adapter |
1 Test tube stopper |
1 Small flask stopper |
1 Pair of tweezers |
1 Fire striker or lighter |
1 Roll of laboratory tape or labels |
2 Pipette bulbs |
1 Pen |