There is such a class of gases, their content in the atmosphere is very small, and very inactive, it is difficult to react with other substances to produce compounds, they are called noble gases, also known as noble gases. Next, we will introduce the least rare of the noble gases, argon (Ar).

Argon is colorless, odorless, cannot burn itself, nor can it help to burn, and its content in the atmosphere is second only to nitrogen and oxygen, and its content is higher than carbon dioxide.

Argon is widely used in our daily life. Because of its chemical inactivity, poor thermal conductivity and other characteristics, one of the most widely used is as a filling gas in lighting technology. Filling the bulb with argon can extend the service life of the filament. In addition, in the electric state, argon can emit blue-violet light, so people often put argon and several other gases that can emit color into the light bulb, used to make neon lights. In addition to lamps, some window glass is also filled with argon. Some of the Windows of the building are equipped with insulating glass, and a layer of gas insulation with good insulation performance is inserted between the glass, which is filled with argon, which can isolate some outside heat, thus greatly reducing the thermal conductivity of the window. This method has now been widely used in the manufacture of hollow layer materials for high-grade insulating glass.

In industrial production, argon is often used as a protective gas for welding or cutting metals: First, in the welding process, due to the heat capacity and thermal conductivity of argon are very small, so the loss of arc heat in argon is very small. In the argon environment, arc cooling is very slow, so the stability of arc combustion is good, can be maintained at a high level, and can be efficiently completed welding. Secondly, because the ionization potential of argon is relatively low, the arc voltage required for welding is also relatively low. In this way, we can use less energy to weld the same amount of parts, thus saving energy. Thirdly, the density of argon is relatively large, about 1.4 times that of air. Argon gas from the nozzle can form a stable layer of gas flow. In addition, argon is denser than air and is not easily dispersed by air, so it can be stably covered on the metal surface and play a good protective role.

Argon also has applications in medicine, such as the argon knife. Argon knife full name is argon plasma coagulation, this treatment method is the use of argon ionization under the action of high frequency current, the argon plasma generated after ionization has electrical conductivity, can direct the current from the high frequency output electrode to the tissue. This method not only avoids direct contact between the electrode and the tissue, but also ensures that the current can enter every corner of the tissue flexibly. When the high-frequency current touches the tissue, it will deactivate and solidify the tissue through thermal effect. In the treatment of tumors, depending on the specific situation, doctors will choose the argon knife as a means of treatment.

As a noble gas, argon's uses are not rare. Although it can't be seen or touched, argon's properties bring us a lot of convenience.