Please explain from the principle of equilibrium movement The higher the pressure, the lower the me

Although we have learned and recognized equilibrium when studying reversible reactions in chemistry, which is what we usually call chemical equilibrium, the theory of equilibrium can be widely applied to many places. Levers and balances are common balances in physics; The dissolution and precipitation of solids are the equilibrium of common physicochemical changes; The critical point of the three-state change of matter is also a physical equilibrium.

The most valuable thing about Le Chatre's principle (the principle of balanced movement) is that "".If changedA condition that affects the balanceBalanceJust to be able toWeaken this changeto move".

Pressurization is to increase the pressure, and the equilibrium movement will be carried out in the direction of decompression, and the direction of decompression is the direction of reducing the volume, the density of ice is smaller than that of water, and the volume is larger than that of water at the same mass. That is, the process of turning ice into water is a process of volume reduction. So, under pressure, the ice easily turns into water, causing the melting point of the ice to become lower.

First of all, do you know that the process of water turning into ice is actually the process of H atoms and O atoms forming hydrogen bonds, and the weak interaction force of hydrogen bonds is more susceptible to external influences than strong interaction forces such as covalent bonds, and the process of ice melting is the process of hydrogen bonds being broken, and in the process of pressurization, a large amount of hydrogen bonds absorb energy, causing hydrogen bonds to be more easily broken, and macroscopically speaking, the melting point is reduced.

As for equilibrium movement, water and ice are physical changes, and the definition of equilibrium movement is applied to chemical changes, and it is impossible to explain them.

The melting of ice into water is a process of volume reduction, and the greater the pressure, the more favorable it is for the equilibrium to move in the direction of water, so the higher the pressure, the lower the melting point of ice.

Melting point is a physical property of a substance. The melting point of a substance is not fixed, and there are two factors that have a great influence on the melting point.

One is pressure, which is usually referred to as the melting point of a substance, which usually refers to the situation at an atmospheric pressure; 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 the process of increasing volume, and when the pressure increases, the melting point of these substances increases; For a substance like water, unlike most substances, the volume of the process by which ice melts into water decreases (as does the metal bismuth, antimony, etc.), and the melting point of ice decreases when the pressure increases.

The other is the impurities in the substance, what we usually call the melting point of the substance, which usually refers to the pure substance. But in real life, most of the substances contain other substances, such as a small amount of other substances in the pure liquid substance, or called impurities, even if the number is small, the melting point of the substance will change greatly, for example, there is salt in the water, the melting point will drop significantly, seawater is the water with salt, and the temperature of seawater freezing in winter is lower than that of river water, which is the reason. The melting point of saturated salt water can drop to about -220, and the northern cities often sprinkle salt on the snow on the highway when it snows heavily in winter, as long as the temperature is higher than -22 at this time, enough salt can always melt the ice and snow, which is also an application of the melting point in daily life.

Microscopic explanation: the melting point is essentially the temperature at which the solid and liquid phases of the substance can coexist and be in equilibrium, taking ice melting into water as an example, the melting point of ice at an atmospheric pressure is 0, and when the temperature is 0, ice and water can coexist, if there is no heat exchange with the outside world, the state of coexistence of ice and water can remain stable for a long time. In various crystals, the interaction forces between particles are different, and therefore the melting point is different. For the same kind of crystal, the melting point is related to the pressure, and the melting point of the substance at a pressure of 1 atmosphere is generally taken as the normal melting point.

At a certain pressure, both the melting point and the freezing point of the crystalline substance are the same. The melting point of a substance that expands in volume during melting increases when the pressure increases.

Lowering the temperature and increasing the pressure can change the conversion rate.

For reactions where the positive reaction is exothermic and the number of reactive molecules decreases, reducing the temperature and increasing the pressure is conducive to improving the conversion rate.

However, for the reaction where the positive reaction is endothermic and the number of reactive molecules increases, reducing the temperature and increasing the pressure is not conducive to improving the conversion rate.

<> Kejingshan, Labo Liang oak, the dragon is like a song.

Answer: (1) The skate blade is very sharp, which can reduce the force area and increase the pressure when the pressure is constant; When the ice surface is pressurized, the melting point decreases, and the ice melts into water, which forms a water film between the skate blade and the ice surface, reducing friction, so the skates can glide quickly on the ice

2) The temperature of the river water is higher than the air temperature, and the temperature difference is large; The evaporation of river water produces a large amount of water vapor; The water vapor meets the cold air and liquefies into small water droplets

There is a wonderful relationship between the melting point of ice and pressure: below 2200 atmospheres, the melting point of ice decreases with increasing pressure, about 1 degree Celsius for every 130 atmospheres of increase; After exceeding 2200 atmospheres, the melting point of ice increases with increasing pressure: the melting point of ice at 3530 atmospheres is -17, at 6380 atmospheres it is 0, at 16500 atmospheres it is 60, and at 20670 atmospheres water freezes at 76, which is called veritable "hot ice".