Why do flowing rivers freeze?

The reason why the flowing river freezes:

When water turns into ice, the movement of water molecules cannot break the hydrogen bond, which plays a major role. It combines water molecules together to form a regular spatial structure. In the crystal lattice, four hydrogen atoms are located at the vertex of the regular tetrahedron, and one oxygen atom is located at the center of the tetrahedron.

In this way, the gap between molecules becomes larger and remains constant, so the volume of water becomes larger when it forms ice; However, in water, molecular movement can not only break the hydrogen bond between water molecules, but also prevent molecules from violently moving and causing frequent collisions between molecules. Molecules can slide and cross each other, thus filling the gaps with each other and increasing the volume.

Generally speaking, rivers will freeze when the temperature is below zero.

Extended data:

There are two situations in which rivers freeze. One is to form shore ice from the shore, develop towards the center of the river, and gradually merge into an ice bridge. The width of the ice bridge expands, making the whole river completely frozen. The other is that after flowing ice forms an ice dam in a narrow or shallow river, it quickly freezes between ice cubes and between ice cubes and river banks, and expands upward against the water flow, thus freezing the whole river surface.

When the temperature rises when spring comes back, the ice in the river begins to melt, and the decomposed ice flows down with the river and the river opens. However, not all river ice is thawed in such a gentle way, so that the river surface can be opened smoothly, and sometimes thawed quickly, especially when the temperature rises sharply or the water level rises sharply, large pieces of ice are surging down, which is easy to cause freezing.

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