2017年7月29日 · Air does freeze just at temperatures and pressures we don't often experience. There is an entire industry around producing and distilling liquid air. You take air and compress it. As a result the air increases in temperature; the air is allowed to cool. Then the air is expanded by venting it into a new chamber. The result is a much colder gas.

2011年5月26日 · It is not ordinary air as that would be too difficult or expensive to store compressed. Anyway, I noticed that when orientated with the spray head upwards, the stuff which exited the nozzle was mostly vaporised immediately with a small amount of liquid residue.

2018年1月17日 · All that matters is the partial pressure of the water vapor in the air. Liquid water will evaporate and ice will sublimate when the partial pressure is below the saturation level. The partial pressure of completely saturated air can be found as the point at which a vertical temperature line intersects the upper boundary of the tan region in the ...

2016年4月28日 · But when the ambient air temperature rises above 0 Celsius, the actual temperature of the objects will not immediately follow because heat transfer takes time. As long as the object's temperature (which is now slowly rising) remains below 0 Celsius, water, moisture from the air etc will freeze on the object, despite the ambient air's ...

2011年8月31日 · For the air out the hole Pout is 0.1013 MPa (14.7 psia) and the (s, P) state of the air out the hole is constant at (6.59, 0.1013) and at this state the temperature is 225 K ( - 55 F). So assuming an isentropic process the temperature of the gas out the hole is 225 K ( - 55 F) which is also the temperature of the gas inside the contained once ...

If you decrease the pressure, the freezing point of water will increase ever so slightly. From 0° C at 1 atm pressure it will increase up to 0.01° C at 0.006 atm.

2024年1月31日 · $\begingroup$ And besides, at the points where the atmospheric conditions are right, the atmosphere does freeze, usually starting with its H2O component. $\endgroup$ – Peter - Reinstate Monica Commented Feb 1, 2024 at 16:02

2016年8月24日 · In the atmosphere, Warm Air carries more water vapor than an equal volume of cold air, so this phenomenon connects heat with humidity. From the above chart, you can see how the warmer the air, the more saturated it may become. The freeezing process starts with the intake of warm, water vapor saturated air.

What is the dominant form of heat transfer between warm water and cold air? If a $100 mg$ drop of water falls through $-40 C$ air, how quickly could it freeze? Is it credible that in very cold weather spit freezes in the half a second it takes to reach the ground?

2023年10月31日 · Instead, the water droplets start to vaporize at a rapid rate due to the large temperature difference between the hot water and the cold air. This rapid vaporization creates the visible cloud of steam that you observe. The Leidenfrost effect is why the water doesn't immediately freeze on contact with the cold air but forms a cloud of steam instead.