Why is the shape of a snowflake a regular hexagonal shape and how is it formed?

Why is the shape of a snowflake a regular hexagonal shape and how is it formed?

Snowflake, a crystal, is the solid precipitation of water vapor in the sky through condensation, the structure changes with the change of temperature, also known as Weiyang flower and Liuchu, a beautiful crystal, it climbs together in a group in the process of falling, and forms snow flakes. The size of a single snowflake is usually between millimeters. Snowflakes are light, weighing only grams individually.

No matter how light and small the snowflake is, how wonderful it is, its crystalline body is a regular hexagonal shape, so the ancients had the saying that "there are more than five flowers of plants and trees, and six snowflakes are alone", and it is recorded in the works of the history of science in the world that it is the earliest to know the hexagonal structure of snowflakes in China.

Xiaoice is changed by the increase of small ice crystals, and the ice molecules are hexagonal for the most, so the formation of snowflakes is mostly hexagonal, and the shape of each snowflake is not exactly the same. The variety of snowflake shapes is closely related to the water vapor conditions at the time of its formation. For hexagonal flake ice crystals, due to the different degrees of curvature on their surfaces, edges and corners, they correspondingly have different saturated water vapor pressures, among which the saturated water vapor pressure on the corners is the largest, followed by the edges, and the smallest on the plane.

In the case of the same water vapor pressure, the condensation growth of ice crystals is also different due to the different saturated water vapor pressures on the surface, edges and corners of ice crystals. If the water vapor in the cloud is not very abundant, the actual water vapor pressure is only greater than the saturated water vapor pressure of the plane, and the water vapor only condenses on the surface, and the formation is a columnar snowflake; If there is a little more water vapor, the actual water vapor pressure is greater than the saturated water vapor pressure on the edge, and the water vapor will condense on the edge and on the surface, because the speed of condensation is also related to the degree of bending, the condensation is faster in places with a large degree of bending, so the condensation on the edge of the ice crystal is faster than that on the surface, and more flakes are formed at this time; If the water vapor in the cloud is very abundant, the actual water vapor pressure is greater than the saturated water vapor pressure on the corner, so that there are water vapor condensation on the surface, on the edge, and on the corner, but the position at the sharp corner is prominent, the water vapor ** is the most sufficient, and the condensation grows the fastest, so it forms more branch-like or star-shaped snowflakes, so it is also known as six out.

In addition, the constant movement of ice crystals and the changing temperature and humidity conditions in which they are exposed make the various parts of the ice crystals grow at different rates, forming a variety of snowflakes.

Hello friends who love life, I am your good friend Xiao K, an intelligent robot with no loss of human wisdom, Xiao K loves popular science, and his doubts become clear. What are you talking about today? Why are snowflakes hexagonal?

Snowflakes are hexagonal for the following reasons:

In the crystallization process, the crystals in the atmosphere tend to grow slowly in the direction of the main crystal axis, while the direction of the three auxiliary axes is much faster, and the ice crystals are mostly hexagonal flakes. When the atmosphere is rich in water vapor, the surrounding water molecules continue to combine to the original wafers, among which the six apex corners of the snow flakes bear the brunt, so that some protrusions and branches appear on the apex corners.

These branches grow to a certain extent and then fork again. The secondary division is at an angle of 60 degrees to the mother branch, and in this way, a six-pointed star-shaped snowflake is formed. Although each snowflake is in the shape of a six-pointed star as a whole, there are many differences in subtle shapes.

Someone has collected snowflakes of different shapes, and found more than 6,000 different kinds of snowflakes in different subtle shapes.

Miscellaneous

In fact, snowflakes are not only flat hexagonal shapes, but also different conditions such as humidity, temperature, and air pressure will shape them into various novel shapes.

For example, a snowflake that forms around 5 may be columnar. There are also shapes such as triangles and irregular particles. In general, the higher the humidity of the air, the faster the snowflakes will grow and the finer the branches.

This is related to the crystalline habit of water vapor condensation crystallization, which belongs to the hexagonal crystal system of snowflakes crystallized by water vapor condensation and ice frozen by natural water. The Xiaoice crystals of the "embryo" of snowflakes in the clouds are mainly of two shapes.

One is hexagonal, long and thin, called column crystal, but sometimes its ends are pointed, like a needle, called needle crystal. The other is in the shape of a hexagonal flake, like a thin slice from a hexagonal pencil, called a flake crystal.

Snow is formed by direct condensation of water vapor from the atmosphere. The low temperature in the cloud-finch finger causes the water vapor to form ice crystals, and when the temperature is low enough, the ice crystals fall to the ground and are still snowflakes, it is snowing. When the snow melts, it absorbs heat, and the heat in the air is sucked away by the snow, and we should be cold.

That's why it's colder when it snows than when it snows.

Snow forms under the condition that the atmosphere contains cold ice crystal nuclei, sufficient water vapor, and a temperature below 0 (freezing).

The sum of the outer angles of the hexagon is 360°.

A regular hexagon is a polygon with six equal sides and six equal interior angles in plane geometry. The inner angles are equal and the hexagons are equal. From the sum of the outer angles of the polygon equal to 360 degrees, an inner angle is 180-(360 6) = 120 degrees, so each inner angle is 120 degrees.

Because it is a regular hexagon, the regular hexagon can be divided into 6 congruent triangles in the center, making the height of the regular triangle, using the Pythagorean theorem to find the height of 3*a 2, the area of each triangle is (3 a) 2 2, so the area of the regular hexagon is (3 2) 3a (where a is the side length).

The hexagonal shape of snow crystals can be subdivided into two categories, one is sheet and the other is columnar. The most beautiful snowflakes that you often see are those six-sided symmetrical flake snow crystals. They usually form at temperatures between -5 and -20 degrees Celsius, with columnar snowflakes consisting of needles and hollow columns, and needle-shaped snow crystals forming at temperatures ranging from -5 degrees Celsius to -5 degrees Celsius.

The special meaning of the regular hexagon:

The six partition walls are exactly the same width, and the angles between the walls are exactly 120 degrees, forming a perfect regular hexagonal geometry. This leads to the mathematical problem of finding a plane figure with the largest area and the smallest perimeter. In 1943, the Hungarian mathematician Taos ingeniously proved that the circumference of a regular polygon is the smallest of all the polygons that are connected by the end of the eye.

But if the pat edge of the polygon is curved, what happens to the New Year? Taos believed that the regular hexagon had the smallest circumference compared to any other shape, but he could not prove it. And until recently, the American mathematician Hale declared:

When considering that the perimeter is a curve.

Whether the curve protrudes outwards or concave inwards, it is proved that the circumference of the graph, which consists of many regular hexagons, is minimal. Regardless of the results of its proof, we can conclude that the regular hexagonal honeycomb structure is a natural selection of natural selection, and it represents the natural fruit of nature's most efficient labor.

Because the basic structure of the snowflake is ice embryos, each ice embryo is composed of 5 water molecules. Four of the water molecules are on the apex corner of one tetrahedron, and one is located in the center of the tetrahedron. Many ice embryos are connected to each other to form ice crystals, and many ice crystals combine to form snowflakes.

Snowflakes come in many shapes and are very beautiful. If you put the snowflakes under a magnifying glass, you can see that each snowflake is an extremely beautiful pattern, and even many artists are amazed. But how are the various snowflake shapes formed?

Snowflakes are mostly hexagonal in shape, and this is because snowflakes belong to the hexagonal crystal system.

Snowflakes in the clouds"Embryos"There are two main shapes of Xiaoice crystals. One is hexagonal, long and thin, called column crystal, next to the late but sometimes its two ends are pointed, like a needle, called needle crystal. The other type is in the shape of a hexagonal flake, like a thin slice cut from a hexagonal pencil, called a flake crystal.

If the surrounding air is less saturated, the ice crystals will grow very slowly and evenly on all sides. As it grows and falls, it still retains its original appearance, and is called columnar, needle-shaped, and flake-shaped snow crystals, respectively.

Since the ice crystals are hexagonal, the snowflakes formed by the ice crystals are also hexagonal. There is a lot of water vapor in the air, and if the water vapor encounters sub-zero temperatures in the air, it will form ice crystals. Ice crystals are tiny, tiny, hexagonal in shape.

When ice crystals float in the air, they become snowflakes when they hit water vapor.

"Han Poems Biography" once recorded: "Where there are five more plants, trees and flowers, and six snowflakes are alone." "That is, the snowflakes are six-petaled and hexagonal.

In fact, this is related to the crystalline habit of water vapor condensation crystallization, and the snowflakes crystallized by water vapor condensation and the ice frozen by natural water belong to the hexagonal crystal system. Crystals, like ice crystals, are one of the hexagonal crystal systems, with the difference that crystals are crystals of silicon monoxide, while ice crystals are crystals of water.

The hexagonal crystal system is composed of four crystalline axes, of which three auxiliary axes intersect each other at an angle of 60° on a base plane, and the fourth axis (the main crystal axis) is perpendicular to the base plane formed by the three auxiliary axes. When water vapor crystallization, if the main crystal axis develops faster than the other three auxiliary axes and extends very long, then the crystal will form a columnar shape; If the main crystal axis develops slowly and is very short, then the crystal forms a sheet. The reason why snowflakes are all hexagonal is because the crystal grows much slower along the main axis than along the three secondary axes.

In addition to hexagonal snowflakes, scientists have also discovered the existence of triangular snowflakes in nature. In order to solve the mystery, scientists simulated conditions similar to natural snowfall in the laboratory to create snowflakes, and by recording various different shapes of snowflake crystals, they finally found that some triangular snowflake crystals still have six sides, but because they are all made up of six sides with three long and three short, they look like triangles. Scientists point out that this situation is generally due to the fact that impurities such as tiny dust particles will cause a certain edge of the snowflake to tilt during the snowflake's fall, and under the action of the wind, the edge of the downward slope will grow faster, thus forming a triangle.

Although the basic shape of a snowflake is hexagonal, there are many differences in subtle shapes. Many snowflake pattern collectors around the world have photographed thousands of snowflakes** and found a large number of different snowflakes. The charm of a snowflake is that although its basic shape is hexagonal, it is almost impossible to find two identical snowflakes in nature, just as there are no two identical people on earth.