Does ice rise below zero?

Yes. It's said in elementary school nature textbooks. In winter, when you cool your clothes outdoors, the water freezes and sublimates into water vapor, and the clothes are dry.

Yes. The direct transformation of the solid state into a gaseous state is called sublimation.

Ice is solid and can sublimate into water vapor at any temperature, although the higher the temperature, the more likely it is for sublimation to occur.

Yes! Just like water at room temperature also evaporates.

Actually, I think it's all a consequence of molecular motion, just like diffusion motion, so as long as the molecules are moving, sublimation is inevitable. It is only in the ideal state of absolute zero that the molecule is at rest.

It's possible. It depends on the pressure Temperature and pressure form a Cartesian coordinate system.

Sublimation occurs at extremely high pressure.

For more precise cases, also refer to the magnetic field.

It will be explained in detail in the book Thermodynamics and Statistical Physics. It also involves the concept of latent heat and critical point of phase change, which is not easy for ordinary people to understand.

Yes, but there will be water vapor that freezes.

The temperature is below zero, and the ice will not melt at all, otherwise the ice sculpture exhibition will not be able to proceed!

Absolutely. Although the temperature is not yet high enough to melt, there are still a small number of ice molecules that get enough energy to sublimate the ice.

For example, when drying clothes in winter, the water on the clothes will first freeze, and then the soldiers will slowly sublimate. In this way, the clothes will also be dried.

It will be sublimated, and in winter, the water on the clothes will freeze first, and then sublimate. Otherwise, how to do it.

No matter how many degrees, the ice will sublimate.

？？Ice will be preserved, a small amount will sublimate, but insignificant.

The physical structure of water is very wonderful, and the volume of ordinary objects will be small when it is solid, but ice will increase. But ice is not raised. Sublimation is only from solids directly to gases. In fact, ice is now liquefied and vaporized.

Obviously, as long as it's not at absolute zero

Yes, the laws of molecular motion say yes.

According to your question, the temperature of ice is generally lower than Celsius, all in minus degrees Celsius, 0 degrees is the intermediate point between above and below zero degrees Celsius, when the ice is at 0 degrees Celsius, the ice crystals have begun to slowly melt from the outside to the inside, so it will definitely melt.

No, that's the case. If it is cooled from water to 0 degrees Celsius, of course, it is not melting, but condensing into ice; Conversely, if the ice (below 0 degrees) warms up to 0 degrees, then the ice melts. Understandable, right?

Freezing at 0 degrees and melting ice is the tipping point.

No, the ice starts to melt at 0, but the melting is endothermic, so 0 is a state of ice-water coexistence.

I've always wanted to do an experiment by changing the air pressure to see if the ice will melt at 0 degrees.

Not necessarily, the ice-water mixture is zero degrees, the temperature rises, the ice melts, and on the contrary, it freezes.

Yes. Just have a little time.

Ice will slowly sublimate at any temperature.

Therefore, as long as the ambient temperature is not above freezing, the ice will sublimate without melting. In winter, the snow cover slowly decreases even if it does not melt, because of the sublimation.

When a dry wind blows through the snow in the mountains, a part of the snow "disappears", and the "disappearance" process does not involve the appearance of liquid water. This is because the snow has sublimated into water vapor.

A concrete example is snow in the Rocky Mountains: when the chinook winds blow from the Pacific Ocean to the Rocky Mountains, the wind is not low (around 15) but dry (less than 10% humidity), and when this wind blows the snow on the mountains, the snow sublimates and no snow water appears.

At minus 15, the molecules still have a certain activity, and the molecules with greater kinetic energy on the ice surface overcome the binding force between neighboring molecules and escape from the ice surface and "sublimate". Freeze-drying (a method of rapid dehydration by vacuuming while freezing) is one of the applications of sublimation, such as the brightly colored dried flowers that we usually see, which are obtained by freeze-drying.

Introduction to SublimationSublimation refers to the phase transformation process of a substance from a solid state to a gaseous state without going through a liquid state. The reverse process is called Ninghua.

In organic chemistry experiments, sublimation is often used to purify products. For example, in experiments with caffeine extraction from tea leaves, the extract was a viscous brown mixture (a mixture of caffeine and multiple organic impurities). To purify caffeine from this mixture, sublimation is used:

Put the mixture into a petri dish, cover the dish with filter paper, press a beaker with water on the filter paper (to make the filter paper cover tightly, and also to cool), then heat the petri dish, stop heating after five minutes, and you will see white crystals on the filter paper, which is pure caffeine.

This is due to the fact that during the heating process, the caffeine sublimates and then condenses on the cooler filter paper to crystallize. The impurities did not sublimate, so they remained in the mixture. In the synthesis of ferrocene experiments, the crude product is heated in a similar way to sublimate and re-coagulate ferrocene.

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According to the query question bank, the temperature continues to rise before the ice melts. True or False) Answer: According to the knowledge of ice melting, before the ice melts, the temperature continues to rise to 0 and it begins to melt. The title is correct. So the answer is: yes.

Ice is ubiquitous in our lives. On December 18, 2019, Professor Bai Guoying's research results were published in Nature, how water burns into ice, and it is not a big circle that is frozen, which confirmed the "classical nucleation theory" in the process of water ice formation for the first time from the laboratory. Although it is confirmed that ice cores need to be formed during the transition of water to ice, the specific structure of ice is not involved.

Ice has 18 three-dimensional crystal structures, of which the hexagonal ice phase collapse is particularly common.

Summary. A: No, the ice will continue to melt in the environment of more than -20 degrees Celsius, until the temperature reaches -20 degrees, the ice will stop melting, but it will not remain at 0 degrees.

The melting temperature of ice is a temperature range that melts between minus 20 degrees and zero degrees, and when the temperature is below minus 20 degrees, the ice will continue to melt without remaining at 0 degrees. The melting temperature of the ice is affected by the external environment, and if the ambient temperature is below -20 degrees, the ice will continue to melt and will not remain at 0 degrees.

A: No, the ice will continue to melt in an environment of more than minus 20 degrees Celsius, until the temperature reaches minus 20 degrees, and the ice will stop melting, but it will not remain at 0 degrees. The melting temperature of ice is a temperature range that melts between minus 20 degrees and zero degrees, and when the temperature is below minus 20 degrees, the ice will continue to melt without remaining at 0 degrees.

The melting temperature of the ice is affected by the external environment, and if the temperature of the outside mountains is below -20 degrees, the ice will continue to melt and will not remain at 0 degrees.

I'm still a little confused, can you be more detailed?

No, because the temperature of the ice in the environment of more than minus 20 degrees Celsius will continue to drop until it reaches the limit, which is the melting point of the ice, which is minus degrees. This is because the melting point of ice is minus degrees, and the temperature of minus 20 degrees is much lower than the melting point of ice, so ice will not remain 0 degrees in an environment of minus 20 degrees. Workaround:

1.Put the ice in an environment where the temperature is controlled below minus 20 degrees Celsius, so that the temperature of the ice can be kept above 0 degrees; 2.Put the ice in an environment where the temperature is controlled above minus 20 degrees, so that the temperature of the ice can be kept below 0 degrees; 3.

Put the ice into an environment where the temperature is controlled at more than minus 20 degrees, so that the temperature of the ice can be kept at about 0 degrees, so as to achieve the purpose of keeping the temperature of the ice at 0 degrees. Personal Tips:1

The melting point of ice is minus degrees, so in an environment of more than minus 20 degrees, the temperature of ice will not remain at 0 degrees; 2.If you want to keep the temperature of the ice at 0 degrees, you can put the ice in an environment where the temperature is controlled at more than minus 20 degrees, so as to achieve the purpose of keeping the temperature of the ice bench pants at 0 degrees.

Zero-degree ice will melt when placed in a zero-degree glucose solution for the following reasons:

The freezing point of a solution is the temperature at which the vapor pressure of the solid-phase pure solvent and the liquid-phase solution is equal. Experiments have shown that the freezing point of refractory non-electrolyte solutions is always lower than that of pure solvents. This phenomenon is known as a decrease in the freezing point of the solution.

This is due to the fact that the vapor pressure of the solution is lower than that of a pure solvent. Glucose is a refractory volatile electrolyte, and its solution vapor pressure is lower than that of pure water, and it will melt when ice is placed at zero degrees Celsius.

Freezing Point:

The freezing point is the temperature at which the crystalline substance solidifies, and is the temperature when the vapor pressure of the liquid is equal to the vapor pressure of the solid, and different crystals have different freezing points. At a certain pressure, the freezing point of any crystal is the same as its melting point. With the same crystal, the freezing point is related to the pressure.

The freezing point of crystals that expand in volume during solidification decreases with the increase of pressure. When solidifying, the freezing point of crystals that shrink in volume increases with increasing pressure. During the solidification process, the liquid transforms into a solid while emitting heat. So the temperature of the substance will be in the liquid state when it is higher than the melting point; When it is below the melting point, it is in a solid state.

Amorphous substances have no freezing point.

Factors for freezing point change:

The melting point (freezing point, the same below) of a substance usually refers to the situation at one atmosphere; If the pressure changes, the melting point also changes. There are two different cases of the change in melting point with pressure. For most substances, the melting process is a process in which the volume increases, and when the pressure increases, the melting point of these substances increases; For substances like water, unlike most substances, the process by which ice melts into water is reduced in volume (as is the case with metal bismuth, antimony, etc.), and the melting point of ice decreases when the pressure increases.

Dissolved with impurities. If there are a small amount of other substances, or impurities, dissolved in the liquid, the melting point (freezing point) of the substance will vary greatly, even if the amount is small. For example, if there is salt in water, the melting point (the temperature at which the solid-liquid phases coexist and equilibrate) will drop significantly, and seawater is salt-dissolved water, and the temperature at which seawater freezes in winter is lower than that of river water. The melting point of saturated salt water can drop to about -22.

No, we know that the temperature of the ice-water mixture is zero degrees Celsius, so 0 ice will not melt.

It stands to reason that no, it's just a cut-off point, but it can't be said that the quality of ice and water in the ice-water mixture remains the same. This is because the rate at which the water is frozen is equal to the rate at which the water freezes. Zero degrees do not freeze, that is, the surface of the water melts at the same time as it freezes.

In the same way, ice at zero does not melt, and the ice surface melts and freezes immediately.

Than a certain amount, melting requires dissolving heat, which means that if you can't absorb heat from the outside, you won't melt.

Straight north and west straight, which one gives way.

Ice will remain as it is at 0 degrees Celsius, and if it is heated again, it will turn watery. The water does not freeze at 0 degrees Celsius, and it freezes when it cools down again.

Not necessarily, to put it simply, there is 0 degree ice in this world, there is also 0 degree water, and the ice-water mixture is also 0 degrees.

If you say that ice rises from minus to zero, then it can be analyzed in terms of energy:

Ice belongs to crystals, and it has a fixed melting point. That is to say, if you heat it from below zero, it will show such a state change: the temperature rises with the heating, rises to zero degrees, and even if it is reheated, the temperature does not change, but changes from the ice form to the water form, and when the ice completely melts into water and continues to heat, the temperature of the water starts to rise from zero degrees.

Is it understandable?

If the partial pressure of water vapor in the air is lower than that of MPa, ice with a temperature below the opening level will directly sublimate into vapor when it absorbs heat from the outside and the temperature rises. Under such conditions, clothes that have been frozen outside in winter will also dry because the ice has sublimated into steam.

Sublimation - The direct change of matter from a solid state to a gaseous state is called sublimation.

Sublimation requires endothermy.

The phenomenon of sublimation is the direct transformation of an object from a solid state to a gaseous state, which does not pass through a liquid state.

The current junior high school physics textbook describes ice sublimation and water vapor condensation: "In winter, wet clothes that are dried outside will form ice, but frozen clothes will also dry because of ice sublimation into water vapor." On cold winter mornings, outdoor objects often hang a layer of frost, which is a Xiaoice particle formed directly by the condensation of water vapor in the air."

That is, the process of crossing this boundary line from the solid phase to the gas phase is called sublimation. Most substances can be condensed into the same solid as before sublimation after sublimation into vapor, but some solids will form a solid with another structure after sublimation and condensation, such as red phosphorus after sublimation and then condensation to become white phosphorus.

Sublimation is the process of endothermy, and the enthalpy absorbed by sublimation is called enthalpy of sublimation or heat of sublimation. The heat of sublimation of the same substance is always greater than the value of the heat of evaporation.

At a certain atmospheric pressure, the temperature at which the vapor pressure of a solid substance is equal to the external pressure is called the sublimation point of the substance at this pressure. At the point of sublimation, sublimation occurs not only on the surface of the solid, but also inside it, and the effect is very intense.