COLORS IN CHEMISTRY




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COLORS IN MODERN ATOMIC THEORY

Fireworks and neon signs are a lot more complicated than explosions and pretty lights. Elements are used to make the different colors in both. When they come in contact with fire or electricity, different elements create different colors.

--Neon Lights
In the neon light's case, this is because when the electricity is applied, the atoms of the noble gases in the tube lose valence electrons and become ions, which bounce around the tube, creating kinetic energy. When these atoms and ions collide, they absorb some of the other's kinetic energy, causing them to be unstable. The unstable atoms and ions release the energy by giving off particle of light called photons. Each gas has a different energy level, so the colors of the light appear different for each. Neons lights are not colored light bulbs, as many people think. (Woodford)

--Fireworks
Fireworks are a bit more complicated than neon lights because pyrotechnicians require the use of gunpower, strings, cases, and chemicals to create dazzling firework displays and effects. Black powder (a mixture of carbon, sulfur, and potassium nitrate; it burns bright yellow) creates the explosive force to launch the fireworks into the air. The technicians have to have a keen knowledge on chemicals in order to make their fireworks. They need to know what wavelength, or color, each compound makes. Just like with neon lights, the compounds in fireworks have electrons than become excited (highest energy level) when heated, and release colored light and energy when they move back to ground state (lowest energy level).

COLORS

--Neon Lights
The colors in neon lights come from the noble gases: helium, neon, argon, krypton, xenon, and radon. When electricity passes through the tubes containing them, they each give off a distict color. Neon glows bright red, krypton is orange, xenon is bright blue, argon mixed with neon makes green, argon and xenon make violet, and yellow comes from argon and mercury.

--Fireworks
Most firework colors come from compounds of elements, the most important being the black powder mentioned above. Strontium chloride (Lithium can also be used) produces a red light, barium chloride produces a burst of green light, calcium deepens colors, and aluminium is used to make the sparks in sparklers. Copper creates a blue explosion, and zinc is used in smoke effects, and so on and so on. They are many, many different compounds and techniques for making fireworks colors.



PRINT SOURCE:
Woodford, Chris. Cool Stuff and How it Works. New York: DK Publishing, Inc., 2005. 256. Print.
PICTURES: http://www.sxc.hu/photo/509879/, http://www.softpicks.net/screenshots/Free-Holiday-Fireworks-Screensaver.jpg

BY LORIN ALLEN