Why does water expand in volume when it freezes?

This is due to the abnormal swelling characteristic of water, which can be explained by knowledge of chemistry. In general, objects obey thermal expansion and contraction, i.e. for the same object "the density of the solid should be greater than that of the liquid." Water, on the other hand, is caused by chemical knowledge.

In general, when the temperature of the object increases, the volume of the object expands and the density decreases, which is commonly referred to as the phenomenon of "thermal expansion and cold contraction". However, when the temperature of water rises by 0, a special phenomenon occurs. Experiments have resulted in a t-curve, which is a curve of the density of water as a function of temperature.

As the temperature rises from 0 to 4, the density of water gradually increases. As the temperature continues to rise from 4 to 4, the density of water gradually decreases. Water has its highest density at 4. Water in the range of 0 to 4 exhibits the phenomenon of "cold expansion and heat contraction", which is called abnormal expansion. The anomalous expansion of water can be explained by the theory of hydrogen bonding and associated water molecules.

The density of a substance is determined by the average spacing of molecules within a substance. For water, because there are a large number of single water molecules in water, there are also associated water molecules that are combined with multiple water molecules, and the average molecular spacing of the associated water molecules formed after the association of water molecules becomes larger, so the density of water is determined by the number of associated water molecules in the water and the number of single water molecules associated. Specifically, the density of water is determined by two factors: the association of water molecules and the thermal motion of water molecules.

When the temperature increases, the thermal movement of water molecules accelerates and the association effect is weakened. When the temperature decreases, the thermal motion of water molecules slows down and the association intensifies. Considering the influence of these two factors, we can know the law of water density change. <>

The fact that water turns into ice and becomes larger is due to the strong hydrogen bonding force between the water molecules in liquid water. It is more than the intermolecular force (van der Waals force......Uh, is that how it is written??? Much bigger.

When water is in a liquid state, under the action of hydrogen bonding force, the water molecules are close together, and it appears to be small in size at the macro level. When it becomes solid, water becomes crystalline, the molecular arrangement becomes regular, the force of hydrogen bonding is weakened, and the macroscopic manifestation becomes larger. Most liquids become solid because the molecules are more closely packed when the object is solid.

However, there is an exception to one category, which is substances that have hydrogen bonds between molecules in the liquid state. <>

First of all, you have to understand that a water molecule is held together by a covalent bond between one oxygen atom and two hydrogen atoms. Although the water molecule is not a linear molecule, because a water molecule is composed of only 3 atoms, the water molecule is a planar structure from an isolated point of view.

Just like the answer on the first floor, the water molecules in liquid water are in a not very chaotic state under the influence of hydrogen bonds. However, once the temperature of the water reaches 4 degrees Celsius, the distance between the water molecules gradually decreases, and the hydrogen bond, which was originally the best supporting role, begins to upgrade to the leading actor who is as important as the covalent bond of hydrogen and oxygen. As the hybridization mode of the water molecule is sp3.

In this way, we see the result of the last diagram in the connection on the first floor: 3 water molecules forming a spatial tetrahedron. In this way, the space utilization rate for the whole water becomes lower, so the volume of the whole water becomes larger.

Thermal expansion and contraction is a principle of physics, so the volume will become smaller after freezing, which is a common phenomenon in physics and is applicable in many places.

This is because the density of ice is greater than that of water. So when the water freezes, the density of ice is formed. The volume is naturally large.

The main reason is that the density decreases after freezing, so the volume expands.

Categories: Education, Science, >> Science & Technology.

Analysis: It is a question of molecular forces vs molecular motion. Water is able to "succumb" to a container to form ice.

The process of water freezing is actually the process of weakening the molecular motion of water due to heat transfer. The movement of the water molecules weakens and eventually freezes. Since the molecular space of ice is larger than the volume of water, the volume of ice is larger than that of water.

Normally, in the range of 0 -4 degrees, the volume of ice expands as the temperature drops. This is the premise of the discussion.

In the process of freezing, as long as the heat transfer process continues, the movement of water molecules will continue to weaken. Therefore, even if the container for water is limited in space to prevent water from acquiring the volume normally of ice, it does not prevent the weakening of the movement of water molecules. That is, if the water is only limited by volume in the process of cooling, it can still become ice.

In the process of becoming ice, if the volume is limited, there will be a contradiction between the molecular force of the ice and the bearing capacity of the container. The difference between the supposed volume of the ice and the actual volume determines how much the ice molecules are compressed, and also how much the molecular force is. The molecular forces of ice follow the law of change in molecular forces (see high school physics books), which is very amazing, but not everything can be overcome.

As long as there is a sufficiently strong container, the container will not be broken.

It can be seen that the process of ice formation is a process of weakening the movement of molecules, and the hardness of the container cannot be stopped. The compression of the ice volume is relative and can be prevented by the container.

It is important to point out that in this case, the energy required for water to form ice is used in two ways: (1) the energy that water normally uses to form ice and (2) the amount of energy required for the ice to be compressed. The latter requires so much energy that one can mistakenly think that "if you put water in a very strong and limited container and then cool it down, you can't form ice".

In fact, ice can be formed, but the process of ice formation is also the process of compressing water (or ice), but the latter process requires a considerable amount of energy.

Summary. Hello, the water freezes into ice and the volume becomes larger, because there is a strong hydrogen bonding force between the water molecules in liquid water, which is much greater than the intermolecular force, when the water is in a liquid state, under the action of hydrogen bonding force, the water molecules are close to each other, and the volume is small on the macroscopic level, and when it becomes solid, the water becomes crystalline, the molecular arrangement has a law, the hydrogen bonding force is weakened, and the macroscopic performance is that the volume becomes larger.

Why does water expand in volume after it freezes into ice?

Hello, the water freezes into ice and the volume becomes larger, because there is a strong hydrogen bonding force between the water molecules in liquid water, which is much greater than the intermolecular force, when the water is in a liquid state, under the action of hydrogen bonding force, the water molecules are close to each other, and the volume is small on the macroscopic level, and when it becomes solid, the water becomes crystalline, the molecular arrangement has a law, the hydrogen bonding force is weakened, and the macroscopic performance is that the volume becomes larger.

Is there any solution to the bulging.

No way. The nature of water is like that.

There's simply no way around it.

It is also possible to turn water into steam, or into ice water, without freezing.

1. This is caused by the particularity of the ice structure, in order to maintain a stable structure, the bond angle of water molecules in the ice increases, and the structure of a regular tetrahedron is formed through hydrogen bonding, and the pores in it increase, so the volume increases. The density of ice is less than that of water, the density of ice, the density of water is 1g cm3.

2. According to the density = mass volume, the water solidifies into ice, the mass does not change, and the density decreases, then the volume increases.

3. Generally, the volume of objects increases when the temperature increases, and the volume decreases when the temperature decreases. If the water is above 4, the segment is noisy, the volume expands and contracts, that is, the volume increases when the temperature rises, and the volume decreases when the temperature decreases. However, when the water is between 0 4, there is abnormal expansion, heat shrinkage and cold expansion, that is, the volume decreases when the temperature increases, and the volume increases when the temperature decreases.