What is a true "neon" light?

Question

I am trying to purchase a true neon light for a demo in my chemistry class to show how gases glow different colors. Someone is trying to tell me that the neon light he is selling is true neon but it does not have clear glass, it is white. That makes me think this is a fluorescent bulb. In the picture it appears green but there could be a little green bulb in the bottom, or something? Do you agree that he doesn't know what he's talking about? Or is it me?

Answer 1

A "true" neon light will have clear glass, if you want to get the specific frequencies that Neon plasma produces.

You friend's light may have neon gas inside, (impossible to tell), but you don't want it if you want to see what neon light looks like.

Answer 2

A "true" neon light is produced when the atoms of neon are zapped causing its electrons to change energy levels. Its color is orange-red. Any other color and you don't have "neon". If you want to see the true color the tube has to be clear.

You can order tubes filled with various gases to demonstrate the colors each element produces but you need a power supply, too. Almost all of the big supplier have them (they're called spectrum tubes; the power supply is called a spectrum tube power supply)- I use Flinn Scientific and Cynmar (Cynmar is a little cheaper).

Answer 3

When neon is excited with electricity, the outer electrons jump up to a higher energy level and then fall back a particular distance, a wavelength of light distance. Neon lights are orange red. They are not any other color. If a different gas is in the tube they are not neon lights.

The tube should be clear, and he should be able to demonstrate it to you that it is red orange.

Answer 4

Red is the color neon gas produces, neon gas glows with its characteristic red light even at atmospheric pressure. There are now more than 150 colors possible; almost every color other than red is produced using argon, mercury and phosphor. Neon tubes actually refer to all positive-column discharge lamps, regardless of the gas filling. The colors in order of discovery were blue (Mercury), white (Co2), gold (Helium), red (Neon), and then different colors from phosphor-coated tubes. The mercury spectrum is rich in ultraviolet light which in turn excites a phosphor coating on the inside of the tube to glow. Phosphors are available in most any pastel colors.

Answer 5

A true neon light shines so brilliantly that it is near-blinding (avoid looking directly at it for extended time). When shining in the dark, it appears to have a glow around it.