# What is a gas mixture? What does the mixed gas do?

Overview of Mixed Gases

A gas containing two or more active components, or a non-active component whose content exceeds the specified limit. ​​
A mixture of several gases is a commonly used working fluid in engineering. Mixed gases are often studied as ideal gases. ​​
Dalton’s law of partial pressures The total pressure p of a mixture of gases is equal to the sum of the partial pressures of the constituent gases. The partial pressure of each constituent gas is the pressure that the constituent gas alone occupies the total volume of the mixed gas at the temperature of the mixed gas.

Composition of gas mixture

The properties of the mixed gas depend on the type and composition of the constituent gas. There are three ways to express the composition of the mixed gas. ​​
①Volume composition: the ratio of the sub-volume of the constituent gas to the total volume of the mixed gas, expressed by ri
The so-called partial volume refers to the volume occupied by the constituent gas alone under the temperature and total pressure of the mixed gas. ​​
②Mass composition: the ratio of the mass of the constituent gas to the total mass of the mixed gas, represented by wi
③ Molar composition: A mole is a unit of quantity of a substance. If the number of basic units (which can be atoms, molecules, ions, electrons or other particles) contained in a system is equal to the number of carbon-12 atoms in 0.012 kg, the amount of matter in the system is 1 mole. The ratio of the moles of the constituent gas to the total moles of the mixed gas, expressed by xi

Properties of mixed gases

When the mixed gas is regarded as a pure substance, it is often used that the density of the mixed gas is equal to the sum of the products of the density of each constituent gas and its volume component under the total pressure and temperature of the mixed gas.

Common gas mixture

Dry air: a mixture of 21% oxygen and 79% nitrogen
Carbon dioxide mixed gas: 2.5% carbon dioxide + 27.5% nitrogen + 70% helium
Excimer laser mixed gas: 0.103% fluorine gas + argon gas + neon gas + helium gas mixed gas
Welding gas mixture: 70% helium + 30% argon gas mixture
High-efficiency energy-saving bulbs filled with mixed gas: 50% krypton gas + 50% argon gas mixture
Childbirth analgesia mixed gas: 50% nitrous oxide + 50% oxygen mixed gas
Blood analysis gas mixture: 5% carbon dioxide + 20% oxygen + 75% nitrogen gas mixture.

Post time: Jun-06-2022