Why does a gas have a critical temperature, and the higher the critical temperature of the gas, the

Various substances have their boiling points, and gases are certainly no exception.

The critical temperature of the gas will change its state...!

Yes, a high critical temperature means that as long as the actual temperature is lower than this critical temperature, it is a liquid state, and it is easy to maintain a liquid state; In the same way, if the critical pressure is high, it is actually easy to keep the liquid at low pressure.

There are two ways to achieve liquefaction, one is to reduce the temperature, the other is to compress the volume, and the critical temperature is the maximum temperature of gas liquefaction.

The critical temperature is the maximum temperature at which a gas can be compressed into a liquid, above which no amount of pressure can liquefy it. The pressure corresponding to this temperature is the critical pressure. The critical phenomenon was first discovered by Andrews in 1869.

There are three phases of any substance: gas, liquid, and solid. The point where the three phases coexist in equilibrium is called the three-phase point.

The point where the liquid and gas phases are in equilibrium is called the critical point.

The temperature and pressure at the critical point are called the critical temperature and critical pressure. Different substances require different pressures and temperatures at their critical points. Since the critical temperature of ammonia is the critical pressure, it can be condensed into a liquid by air and water at room temperature in the condenser under normal refrigeration conditions.

However, the critical temperature of R13 is only, so it is difficult to liquefy it if it is cooled by air and water under normal conditions, so it is more appropriate to choose some refrigerants with high critical temperature in the usual refrigeration device.

Some substances, such as ammonia, carbon dioxide, etc., have a critical temperature higher than or close to room temperature, and such substances are easily compressed into liquids at room temperature. Some substances such as oxygen, nitrogen, hydrogen, helium, etc. have a very low critical temperature, among which the critical temperature of helium is -268. In order to liquefy these gases, it is necessary to have a certain cryogenic technology to enable them to reach their respective critical temperatures, and then liquefy them by increasing the pressure.

1.To put it simply, the critical temperature is the maximum temperature at which a gas can be compressed into a liquid, above which no amount of pressure can liquefy it.

2.The ground pressure corresponding to this temperature is the critical pressure.

Years Andrews first discovered the critical phenomenon. There are three phases of any substance: gas, liquid, and solid.

4.The point where the three phases coexist in equilibrium is called the three-phase point.

5.The point where the liquid and gas phases are in equilibrium is called the critical point.

6.The temperature and pressure at the critical point are called the critical temperature and critical pressure.

7.Different substances require different pressures and temperatures at their critical points.

Critical. 1) Definitions or Interpretations.

The temperature at which the substance is in a critical state.

The maximum temperature at which a substance appears in liquid form.

2) Description. Every substance has a specific temperature, above which the gaseous substance will not liquefy, no matter how much pressure is increased, and this temperature is the critical temperature. Therefore the substance is to be liquefied; The first thing to do is to find a way to reach its own critical temperature.

Some substances such as ammonia, carbon dioxide.

etc., their critical temperature is higher than or close to room temperature, and such substances are easily compressed into liquids at room temperature. The critical temperature of some substances such as oxygen, nitrogen, hydrogen, helium, etc. is very low, and the critical temperature of helium is one, to liquefy these gases, there must be a certain low-temperature technology to make the car energy.

They reach their respective critical temperatures, and then liquefy them by increasing the pressure.

Gaseous substances above the critical temperature are usually called gases, and gaseous substances below the critical temperature are called vapors.

Critical. The temperature at which a substance is in a critical state is called the "critical temperature". Cooling and pressurization are the conditions for liquefaction of gases.

However, only pressurization may not liquefy the gas, depending on whether the gas is below the critical temperature at that time. If the temperature of the gas exceeds the critical temperature, the gaseous substance will not liquefy no matter how much the pressure is increased. For example, the critical temperature of water vapour is 374, which is much higher than the normal temperature, so it is very easy for water vapour to cool into water.

Others, such as ether, ammonia, carbon dioxide, etc., have a critical temperature higher than or close to room temperature, and such substances are easily compressed into liquids at room temperature. However, there are also some substances with very low critical temperatures, such as oxygen, air, hydrogen, helium, etc., which are extremely difficult to liquefy. where the critical temperature of helium is -268

To liquefy these gases. It is necessary to have certain cryogenic technology and equipment to bring them below their respective critical temperatures, and then liquefy them by increasing the pressure.

Gases with a critical temperature lower than normal temperature are compressed gases, and gases with a critical temperature higher than normal temperature are liquefied gases. Compressed gases are completely gaseous when pressurized at -50, including gases with a critical temperature below or equal to -50.

High-pressure (low-pressure) liquefied gases refer to gases that are partially liquid when pressurized at temperatures higher than -50, including high-pressure liquefied gases with a critical temperature between -50 and +65 and low-pressure liquefied gases with a critical temperature higher than +65.

means a gas that is compressed, liquefied or dissolved under pressure and shall be one of the following two conditions:

1) Compressed or liquefied gases with a critical humidity lower than 50, or a vapor pressure greater than 294 kilopascals (kpa) at 50;

2) compressed gas with an absolute pressure of more than 275 kilopascals (kpa) at temperature, or more than 715 kilopascals (kpa) at temperature; or liquefied gas or pressurized dissolved gas with a vapor pressure greater than 275 kilopascals (kpa) at 3.

The above content refers to Encyclopedia - Compressed Gas.