The Spark of Fireworks

Fireworks are seen year-round and have become a staple in large-scale celebrations. New Year’s Eve and July 4th are two of the most notable examples of fireworks. The fireworks fill the night sky with bright and vibrant colors, but how do fireworks work? How do scientists know what element to use to achieve different colors? At the base of all fireworks is black powder, composed of potassium nitrate, carbon, and sulfur, which when ignited releases immense heat, causing gasses to expand and eventually send little pellets of metallic powder into the air (Brockmeier, 2019). 

As the pellets fly into the sky, the energy released by the black powder puts the electrons inside the metal into a state of “excitement.” However, atoms naturally seek to be in a state of stability, in order to revert to this state, the electrons will get rid of the excess energy by emitting wavelengths. These wavelengths present themselves as colors. Each element has distinct spacing between its energy levels. The metals that have larger spacing between the energy levels will emit shorter wavelengths, which often present themselves as blues and purples. Conversely, atoms with shorter distance between the energy levels will emit longer wavelengths which tend to be oranges and reds (Lutz, 2019). Understanding the science behind fireworks allows us to appreciate even more the bright and colorful displays that light up joyous occasions.

References: 

Brockmeier, E. K. (2019, July 1). The chemistry behind fireworks. Penn Today. Retrieved April 1, 2024, from https://penntoday.upenn.edu/news/chemistry-behind-fireworks

Lutz, A. (2019, July). Exploding Colors: The Science Behind Fireworks. The College Today. https://today.cofc.edu/2019/07/01/fireworks-fourth-of-july