This gas is called noble because of the fact that it practically doesn’t react with any substances, which means it does not give or attach electrons.Neon is a colorless gas, with no taste or smell, the content of which in the atmosphere is 126 ppm, percent by mass.
Since neon has no chemical compounds, let’s talk about its physical properties. By passing high voltage through the gas, it begins to glow with a red-orange light, the luminescence intensity will depend on the voltage and the gas pressure.
The gas pressure In this vial is about one hundredth of the atmospheric pressure, this is done in order to reduce the voltage required for the illumination of the gas in discharge current.The neon atoms are excited by the collision with electrons in the same way as the man who was pushed in a rough way in a crowd.
The electrons in the atom of neon are not inclined to wander around, therefore, after the excitation the atom relaxes and the electron goes back to its place.At high voltage electrons are seeking to fly out from the electrode, i.e. the cathode. When being approached by a neon vial electrons fly out of the metal wire, part of them passes through the glass and begins to encounter molecules of neon inside the vial.