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Neon is a chemical element; it has the symbol Ne and atomic number 10. It is the second noble gas in the periodic table. [ 14 ] Neon is a colorless, odorless, inert monatomic gas under standard conditions , with approximately two-thirds the density of air.
A General Electric NE-34 glow lamp, manufactured circa 1930. Neon was discovered in 1898 by William Ramsay and Morris Travers.The characteristic, brilliant red color that is emitted by gaseous neon when excited electrically was noted immediately; Travers later wrote, "the blaze of crimson light from the tube told its own story and was a sight to dwell upon and never forget."
The color of the light depends on the gas in the tube. Neon lights were named for neon, a noble gas which gives off a popular orange light, but other gases and chemicals called phosphors are used to produce other colors, such as hydrogen (purple-red), helium (yellow or pink), carbon dioxide (white), and mercury (blue). Neon tubes can be ...
These lights are called after neon but often contain other gases and phosphors, which add various hues to the orange-red color of neon. Xenon is commonly used in xenon arc lamps , which, due to their nearly continuous spectrum that resembles daylight, find application in film projectors and as automobile headlamps.
Each type of neon tubing produces two different possible colors, one with neon gas and the other with argon/mercury. Some "neon" tubes are made without phosphor coatings for some of the colors. Clear tubing filled with neon gas produces the ubiquitous yellowish orange color with the interior plasma column clearly visible, and is the cheapest ...
Several of the CPK colors refer mnemonically to colors of the pure elements or notable compound. For example, hydrogen is a colorless gas, carbon as charcoal, graphite or coke is black, sulfur powder is yellow, chlorine is a greenish gas, bromine is a dark red liquid, iodine in ether is violet, amorphous phosphorus is red, rust is dark orange-red, etc.
The color of chemicals is a physical property of chemicals that in most cases comes from the excitation of electrons due to an absorption of energy performed by the chemical. The study of chemical structure by means of energy absorption and release is generally referred to as spectroscopy .
The principle of the atomic emission spectrum explains the varied colors in neon signs, as well as chemical flame test results (described below). The frequencies of light that an atom can emit are dependent on states the electrons can be in. When excited, an electron moves to a higher energy level or orbital.