Neon
All of us have seen the use of neon. On the other hand, what do we know about the neon element? What is it? Where is it located? How do we put it into usable form?
Neon is an element found in a gaseous form. Neon is rare on Earth, however it is quite abundant in the universe. In fact, it ranks fifth among the most abundant elements in the universe. Earth has less due to neon’s light weight and its inherent chemical nature. Volcanic gas contains large amounts of neon.
Our atmosphere contains some neon and it can be extracted by a method called absorption. In this method, air is supercooled to temperatures below 441 degrees F so that it becomes a liquid. When this is passed over carbon, the neon molecules stick to the carbon. If the temperature rises, the neon can “evaporate” and be captured. Since air does not contain as much neon, it is necessary to process 88,000 pounds of liquefied air to make one pound of neon.
Neon is a first class conductor of electricity and for this reason and for having an amazing capacity to emit light that can be seen at great distances, its most frequent uses are in airplane beacons, in lamps and in advertisements. Some pilots have reported seeing neon beacons twenty miles away when it was impossible for them to see other types of lights. The neon light can be seen through the fog.
There are two types of neon that are commonly used. One of them is incandescent discharge lamps, which are small in size and can work at low voltage. Popular uses for these lamps are in circuit test equipment and power indicators. The other type works with a very high voltage and is widely used in advertising signs. Neon is used commercially as a popular coolant because it is less expensive than helium. In liquid form it is very expensive and difficult to obtain when used for testing.
The bright red signs we see are glass tubes shaped like letters or numbers and filled with neon gas. A few drops of mercury are added to the glass to produce a blue light in the signs. When all the air is removed from the glass tubes and they are filled with neon, a neon lamp is created. Sending an electrical current from the electrode at one end of the tube through the neon to a second electrode causes the gas to glow a deep red. Neon lamps, unlike incandescent lamps, do not have filaments since it is the gas that glows. It only takes a quarter of neon to light up 200-300 feet of glass tubing.
This light strikes a variety of light-emitting phosphorescent materials that are coated on the inside of the glass tube, thus producing various colors. To create a blue light, the glass is left transparent. For the creation of special color effects, xenon, krypton and helium gases are sometimes used.
There is great demand for neon, particularly due to its wide use in advertising, in addition to a host of other beneficial uses. This makes neon production a highly profitable business for the most part. The danger with neon occurs when it is allowed to reach high concentrations. In such cases, it displaces oxygen in the lungs of humans, which usually results in death.
For commercial purposes, neon is obtained from the air. For industrial use, neon is produced by fractional distillation of liquid air through the cryogenic method. It is colorless, odorless and tasteless. Pure neon costs $33. per 100 grams. Neon, due to its many useful benefits, has become a part of American life. It is unfortunate that it is only available in small quantities as the demand for neon is very high.
Without neon there would be no neon signs that would harm the public and businesses alike. Since most of the use of neon is for neon signs that generate revenue for businesses and save buyer time and money, its absence would be detrimental to both parties. In fact, there are many other valuable uses for neon that are not well known to the public. The use of neon in wavemeter tubes, television tubes, and helium-neon lasers would be lost. Also, it would lose its use in certain refrigeration applications instead of the more expensive liquid helium.