Effect of liquefaction temperature

Ambient temperature has a great influence on its liquefaction speed. Under a certain pressure, the "liquefaction temperature" of the same substance is basically the same as its "boiling point". So the colder it is, the faster it liquefies.

As we all know, the change of the same substance from gas to liquid and from liquid to gas is the opposite process, or take water as an example. As can be seen from Figure 1, the liquefaction temperature of water vapor is 1 00℃ at 1 standard atmospheric pressure, and the saturated water vapor pressure of water vapor below 100℃ (inclusive) does not exceed 1 standard atmospheric pressure. However, at 1 standard atmospheric pressure, water boils when the water vapor saturation pressure is equal to the external pressure, so the FE section of the state indicates that the water is in a boiling state. Obviously, at a standard atmospheric pressure, the liquefaction temperature of water vapor and the boiling point of water are both 100℃.

At this point, we can also do the following qualitative analysis. Because when the liquid boils, the temperature remains the same until it is liquefied and completely gasified, and then, if it continues to absorb heat, the temperature will rise. Therefore, at the temperature above the boiling point, the substance is completely gaseous and cannot be liquid. That is to say, the gas above the boiling point cannot be liquefied. Only when the temperature drops to the boiling point can the gas become liquid and begin to liquefy. This is the upper limit temperature at which the gas can be liquefied-liquefaction temperature. Obviously, the boiling point and "liquefaction temperature" of the same substance under a certain pressure are the same, and they all increase with the increase of pressure. It is equivalent to the relationship that the melting point and freezing point of the same substance are the same under certain pressure.