UV Beads

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As a child, I would go to church and make bracelets and I would get these little beads that I never paid much attention to. Uv beads are the tiny white beads used for bracelets that change color in the light.  As someone could have guessed it is in the Uv light that the uv beads change colors. The beads can change up to 50,000 times until it is no longer affected by the uv light. Uv beads are also used to detect whether or not a sunscreen is good enough. There is a chemical inside the uv beads that make them change color. There has to be a 300-400 electromagnetic radiation in order for the beads to change.  The dye molecules found in the beads are made up of two conjugated systems. They form into one system. According to a source “When excited with UV radiation, the resulting larger planar conjugated molecule absorbs certain wavelengths of visible light resulting in a color” (1) This seems very exciting as I never knew the beads I used as a child were up beads. I presumed the beads came in those colors. Although they can change color according to the same source it says that “heat from the surroundings provides the activation energy to change the molecule back to its colorless structure” (1) They can serve as colorful beads for one project and return to white beads for another project. Liquid nitrogen can make beads not be able to turn back to their original white color. UV beads are a cheap way to have uv detectors. I also believe using Uv beads are a great way for children to learn about uv and electromagnetic radiation. I did not find that uv beads were used in any other studies to test things out. It would be nice to see if uv beads served a better purpose and could be used more.

Source:

(1) Bell, Jerry A. “Visualizing the Photochemical Steady State with UV-Sensitive Beads.” J. Chem. Educ. Journal of Chemical Education 78.12 (2001): 1594. Web.

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