1, make electric illuminant. The noble gases emit different colors of light when they are energized.

The first neon lights in the world were filled with neon. The red light from the neon lamps is very strong in the air and can pass through thick fog. Therefore, neon lamps are often used in airports, ports, and land and sea lines. The tube is filled with argon or helium and emits light blue or light red light when energized. Fill the tube with a mixture of helium, neon and argon of different contents, and you can make a colorful neon lamp.

People commonly used fluorescent lamps, is in the tube filled with a small amount of mercury and argon, and in the inner wall coated with fluorescent substances (such as calcium halide) and made. When electrify, inside because mercury vapor discharge and produce ultraviolet ray inside, excite fluorescent material, make it gives out the visible light of approximate daylight, call fluorescent lamp again so.

The high pressure long arc lamp filled with xenon gas can give out tens of thousands of times stronger strong light than fluorescent lamp when energized, so it is called "artificial little sun", can be used in squares, stadiums, airports and other lighting.

Neon, krypton and xenon are also used in laser technology.

2, medical treatment.

Xenon lamps have high levels of ultraviolet radiation and can be used in medical technology. Xenon can dissolve in the lipid of the cytoplasm, causing the cells to anesthetize and expand, thus temporarily stopping the function of nerve endings and achieving the effect of anesthesia. A mixture of 80% xenon and 20% oxygen was tried as a side-effect-free anaesthetic. Isotopes of krypton and xenon are also used to measure blood flow to the brain.

3, for protection gas. The chemical properties of the noble gases are very inactive.

When welding precision parts or active metals such as magnesium and aluminum, argon is often used as shielding gas to isolate the air and prevent the metal from reacting with other substances at high temperature.

The plutonium, which oxidizes rapidly in the air, also needs to be machined under the protection of argon. Argon gas in the bulb can reduce the vaporization of tungsten wire and prevent the oxidation of tungsten wire, so as to extend the service life of the bulb.

4, inflation.

Helium is the lightest gas except hydrogen, which cannot be burned and does not aid combustion. However, hydrogen is flammable and explosive. Helium has been used instead of hydrogen to fill balloons and gas boats.

5, Make artificial air.

Helium is mixed with oxygen to make artificial air for divers to breathe. Because in the deep ocean, where the pressure is higher, breathing with ordinary air, there is more nitrogen dissolved in the blood. When a diver rises from the depths of the ocean and gradually regains normal pressure, nitrogen dissolved in the blood is released to form bubbles that clog the microvessels, causing "gas congestion." Helium, on the other hand, is much less soluble in the blood than nitrogen, so replacing ordinary air with a mixture of helium and oxygen (artificial air) would prevent this.