Has the arrangement of water molecules changed to ice? Why?

Definitely something has changed. When water freezes and grows in size, it must be due to a change in the molecular structure inside.

The hydrogen bonds in the water molecule become more numerous, so the volume becomes larger.

It is determined by the special structure of hydrogen bond association between water molecules. According to recent X-ray studies, it has been proved that ice has a tetrahedral crystal structure. This tetrahedron is formed by hydrogen bonding, which is an open relaxation structure, because five water molecules cannot take up the volume of all tetrahedra, and hydrogen bonds in ice connect these tetrahedra into a whole.

This directional and orderly arrangement formed by hydrogen bonding is less space-efficient, accounting for about 34, so the density of ice is small, about 4 degrees Celsius is 9 10 of liquid water. When water dissolves, a large number of hydrogen bonds are disassembled, so that the whole is divided into tetrahedral groups and scattered smaller "water molecule groups" (that is, some associated molecules formed by the association of hydrogen bonds), so liquid water is no longer completely ordered like ice, but has a certain degree of disordered arrangement, that is, the distance between water molecules is not fixed as in ice, and H2O molecules can enter another microcrystalline from one tetrahedral. In this way, the intermolecular voids are reduced, and the density is increased relative to ice.

When the temperature increases, the tetrahedral group of water molecules is continuously destroyed, and the disordered arrangement of the molecules increases, so that the density increases. But at the same time, the thermal motion between molecules also increases the distance between molecules, which reduces the density. These two contradictory factors reach equilibrium at 4 o'clock, therefore, the density of water is highest at 4 o'clock.

After 4, the thermal motion of the molecules increases the distance between the molecules, and the density of the water begins to decrease again.

Water freezes in volume because the spacing between water molecules increases:

1) The water molecules in liquid water are arranged irregularly, and after solidification, the arrangement becomes regular, and due to the action of hydrogen bonding, a tetrahedral structure is formed between the water molecules, which makes the void between the water molecules larger, so the volume of water increases after it becomes ice;

2) Since the water molecule width is a highly polar interosmotic molecule, it can be combined into an association molecule (a combination of multiple water molecules) through hydrogen bonding.

3) Ice has a tetrahedral crystal structure.

As the structural form of the molecule changes, the interval becomes larger.

Summary. Yes, dear, the density of water after freezing is indeed lower. Ice is more spaced between molecules than in water. This is due to the special structure of the water molecule and the formation of hydrogen bonds.

The density of water becomes smaller when it freezes, and the spacing between molecules in ice is larger than that of water, right, and why.

Yes, dear, the density of the water knot cave after the ice is indeed low. Ice is more spaced between molecules than in water. This is due to the Turner structure of water molecules and the formation of hydrogen bonds.

In liquid water, the water molecules are relatively closely arranged, and the bridge or shed molecules are close to each other. When the water is cooled to near freezing, the molecular movement slows down and the water molecules gradually form a regular crystal structure, i.e., ice. In ice, water molecules are arranged in hexagonal lattices, which form a stable structure.

In ice, hydrogen bond formation between water molecules is more stable than in liquid water. Hydrogen bonding is a weak interaction force between water molecules, which will cause the distance between the molecules to increase appropriately. As a result, the distance between the water molecules in the ice is relatively large, resulting in a lower density or degree of ice than that of liquid water.

This special property allows ice to float on the surface of liquid water, maintaining a relatively stable temperature at the bottom of the water body, and playing an important role in protecting underwater life.

What is the relationship between the molecular spacing between crystals and liquids, solids, and gases?

The magnitude relationship between the molecular spacing between crystals, solids, and liquids can be described as:1Crystals:

Crystals are made up of ions, atoms, or molecules arranged periodically. Its molecular spacing is very small and ordered, and the molecules are tightly packed together in a regular manner. 2.

Solids: Solids have smaller molecular spacing than crystals. Solid molecules or atoms have a certain arrangement structure in space, but they do not have the complete periodicity of a crystal as a rent.

3.Liquids: Liquids have a larger molecular interval than solids.

The molecules or atoms of a liquid do not have a fixed arrangement structure, they can move and flow freely, but the interaction between molecules is still relatively tight. 4.Gas:

The molecular spacing of gases is maximum. There is little interaction between the molecules or atoms of the gas, they move at high speed and have large intervals that can be freely diffused within the container. Thus, the molecular spacing of crystals is minimal and ordered, that of solids is slightly larger, that of liquids is larger, and that of gases is maximum.

The molecules themselves do not change when the water freezes.

The formation of ice in water is just a change in the state of water from a liquid state to a solid state, but the state has changed, which is a physical change. For substances made up of molecules, in the process of physical change, the molecules themselves do not change, but the intervals between the molecules change.

Water is made up of water molecules.

For a substance that is made up of molecules, the molecule is the smallest particle that retains its chemical properties.

No, the essence of water freezing is only a change in the spatial structure between water molecules, not a change in the structure of water molecules.

The molecule itself does not change.

Generally, when water and ice are phase-changing, the temperature is the same, and we only count the latent heat. The latent heat here refers to the amount of change in the enthalpy of melting of the object, where the enthalpy is defined as h = u + pv + mu is the internal energy, p and v are the pressure and volume of the system, mu is the chemical energy, and n is the number of particles. When water freezes, it is the time when the phase change occurs, at the moment, the temperature, pressure and chemical energy of water and ice are the same, so when water becomes ice (liquid becomes solid), because the structure is different, work needs to be done, latent heat deducts the work done, and the rest is internal energy, but this is water and ice"Both"The total internal energy of a substance.

Basically, internal energy is not a good parameter to describe phase transitions, because water and ice can be considered as two different substances here. In addition, it is not easy to understand the dynamics of structural transformation in the process, so it is easier to describe the latent heat at a certain pressure, such as the latent heat of melting of water at one atmosphere cal g.

When ice melts into water, the volume decreases, and the interval of the water molecule becomes smaller, and the volume and mass of the water molecule remain unchanged

Therefore, choose B

Ice fiber and water are different states of the same substance, with different physical properties, correct;

Ice and water both. is made up of water molecules.

Constituted, the molecule is to maintain the chemical properties of the substance.

The smallest particles, chemically identical, are wrong;

Both ice and water are made up of water molecules, and the constituent molecules are the same, correct;

Ice and water are different states of the same substance, are the same substance, false;

They are all colorless, identical, wrong

Therefore, c

a. The number of water molecules in the snowflakes of different brothers is very large, resulting in no two finches containing snowflakes in the world, which is correct;

b. When the snowflakes are formed, the water molecules are still in constant motion, which is incorrect;

c. When the snowflakes melt, the spacing between the water molecules changes, which is incorrect;

d. In different snowflakes, the water molecules are the same, so the chemical properties are the same, and this option is incorrect

Therefore, a