Research project “Why is snow white? Why is snow white? We will tell you Why the water is transparent and the snow is white.

Marina Shkerina
Research project "Why is snow white?"

The project was carried out together with the child.

Introduction

Winter came. It became cold outside. The whole earth, all the trees were covered with a white fluffy blanket. White snowflakes fall, fall on the ground, on the roofs of houses, on trees, on people. Snowflakes are like white stars. They quietly fall to the ground.

I really love looking at snowflakes. They're very beautiful. Like lace, all different. Sometimes they stick together and fall to the ground in large flakes. Sometimes the cold wind breaks white stars, turning them into fine snow dust, and then it is very difficult to see them.

One morning I woke up and looked out the window. I saw that everything around: the ground, trees, roofs of houses, became white. It was the first snow that fell. I thought: "Why is the snow white?" And I decided to investigate this problem.

This problem made it possible to formulate the research topic: "Why is snow white?"

Having decided on the topic, I set myself a goal: to study and conduct experiments to answer the question "Why is snow white?"

To achieve this goal, you need to solve the following tasks:

1. Study the literature that talks about snow.

2. Prove experimentally "Why is snow white?"

3. Summarize the knowledge gained.

Object of study: snow.

Subject of study: snow composition

Hypothesis: suppose the white color of the snow is related to the reflection of light.

Research methods:

1. Study of literature on the topic

2. Observation of the research object

3. Conducting experiments

4. Analysis of the results and conclusions of the study

Chapter I. Theoretical substantiation of experimental work.

1.1 What is snow?

What is snow? There are many, many beautiful snowflakes; they fall and fall from a height on the ground, on trees, on the roofs of houses - clean, fragile, sparkling. And then it fell - this amazing snow. He lay down with "magnificent carpets" and covered the ground with a white veil. The snow that fell covered all the pits and ditches, leveled the bumps - completely transformed the plain. The forest has changed even more. The snow scattered in white tufts on the branches of the trees, covered the leaves and twigs that had fallen to the ground with a white blanket, and settled in tall snowdrifts in the bushes. To an attentive eye, he revealed many secrets of forest life - everything that happened was imprinted on the snow cover, left footprints in the snow.

I found the meaning of the word "snow" in the "Modern Explanatory Dictionary". Snow is solid precipitation consisting of small ice crystals that fall out of clouds at temperatures below 0C. Snow forms when water vapor in the atmosphere freezes. Tiny crystals appear first. Following the air currents, they move in all directions. Gradually the crystals “stick” to each other until there are a hundred or more of them. When the sizes of the frozen pieces of ice are large enough, they begin to sink to the ground. We call these clusters of ice snowflakes.

1.2 Where do snowflakes come from?

A snowflake is a frozen crystal of water that has the shape of a six-rayed polyhedron.

Water vapor rises high above the ground. It is very cold at the top, and ice crystals form from it. They are very small. These are not snowflakes yet. Falling down, the crystals rapidly increase. This is because there is a lot of water vapor in the air, which settles on their surface and freezes. So the crystal ice becomes a beautiful, delicate snowflake.

There are so many snowflakes and they are all different - no one is the same.

The largest snowflake ever recorded had a diameter of 12 cm. Usually, snowflakes are about 5 mm in diameter with a mass of 0.004 g.

The crystals that make up the snowflakes have a specific shape. It is either a six-pointed star or a thin plate shaped like a hexagon. The point is that the main water crystal has the shape of a regular hexagon in the plane.

In 1885, American farmer Wilson Bentley obtained the first successful photograph of a snowflake under a microscope. He has been doing this for 46 years and has taken more than 5,000 unique photographs. On the basis of his work, it was proved that there are no two identical snowflakes.

Crystals of different shapes are formed at different temperatures

The most beautiful snowflakes fall where the climate is harsher - for example, in the north.

Depending on the weather conditions, “own” snow falls in different places.

For the formation of large flakes of snowflakes, complete calm is necessary, the longer the snowflakes travel, the more they collide and adhere to each other.

At low temperatures and strong winds, snowflakes collide in the air, crumbling and falling to the ground in the form of fragments - "diamond dust".

1.3 Classification of snowflakes.

Prisms - there are both 6-sided plates and thin posts with a 6-sided section. The prisms have tiny dimensions, they are almost invisible to the naked eye. The facets of the prism are very often decorated with various complex patterns.

Needles - thin and long snow crystals, they form at a temperature of about -5 degrees.

When viewed, they look like small blonde hairs.

Dendrites - or tree-like, have pronounced branching thin rays. Most often these are large crystals, they can be seen with the naked eye. The maximum size of a dendrite can be up to 30 cm in diameter.

12-ray snowflakes - sometimes the columns with tips are formed with the rotation of the plates relative to each other by 30 degrees. When rays grow out of each plate, a crystal with 12 rays is obtained.

Hollow posts- it happens that cavities are formed inside the columns with a hexagonal section. Interestingly, the shape of the cavities is symmetric about the center of the crystal. You need a lot of magnification to see half of the small snowflakes.

Fern-like dendrites - this type is one of the largest. The branches of stellate dendrites grow thin and very frequent, as a result, the snowflake begins to look like a fern.

Irregular crystals- Snow crystals are often small, asymmetrical and accrete with each other. To get beautiful symmetrical crystals, you need a good combination of many weather conditions.

Triangular crystals - such snowflakes form at a temperature of about -2 degrees. In fact, these are hexagonal prisms, some of the sides of which are much shorter than others. But on the edges of such rays can grow.

Bullet sockets - sometimes during the formation of crystals, they can grow together and grow in random directions. Such formations are easily broken into separate crystals, similar to bullets. Hence such an unusual name.

1.4 Why is snow white?

When a Russian is asked to imagine winter, the first thing he sees in his imagination is snow, a snow-white cover that has enveloped everything around. We are so used to the color of the snow that we don’t even think about why the snow is white. It turns out that all the colors we perceive are dependent on the sun's rays. Black objects completely absorb sunlight, and therefore are perceived by us as black. And if the object completely reflects the ray of the sun, then the color will seem to us white.

Snow is frozen water, and as we know, ice is colorless. Why is the snow white? From the Internet and the children's encyclopedia "Everything about everything" I learned that snowflakes are 95% air. The crystals of snowflakes are not smooth, but have edges. The reflection of light from the edges of these crystals makes the snow white. The ice remains colorless, as it passes the entire sunbeam through itself. And every snowflake would let all the light pass through itself and would also have no color. But snowflakes usually fall on top of each other in a chaotic motion. And together they become opaque, and white. To understand why the snow is white, why it reflects the rays of the sun, we need to look at the composition of the snow. Snow is formed from snowflakes, and snowflakes are formed from a huge number of crystals. These crystals are not smooth, but faceted. This is the answer to our question, why is snow white. It is from the edges that sunlight is reflected. Water in the atmosphere is vapor, it freezes, and transparent crystals are formed. The crystals move freely up and down from the movement of air. In this chaotic movement, the crystals connect with each other. And when, finally, too many crystals gather together, then they begin to fall to the ground in the form of snowflakes we are used to. It turns out that the color of the snow is white, because the light of the sun that it reflects is also white. Think if a ray of the sun turned green or yellow, then the color of the snow was the same. Surely, many have noticed that during sunrise or sunset, it seems to us that the sun's rays become pinkish, so the snow at this moment seems to us pink.

Interesting Facts:

# 1: Did you know that snow isn't always white? In many regions of the world, people have seen it red, green, blue and even black! The reason for this variety of colors is tiny bacteria, fungi, and dust in the air that is absorbed by snowflakes when they fall to the earth's surface.

Conclusion on Chapter I

1. I learned that snow is solid precipitation made up of small ice crystals.

2. Each snowflake is a collection of small pieces of ice.

3. Snow is formed from snowflakes, and snowflakes from a huge number of crystals.

Chapter II. Organization of experimental work

on the problem "Why is snow white?"

From my observations, while studying the literature, I learned that any snowflake has the shape of a six-pointed star. Regardless of the shape of the snowflakes, they are all white. And the snow is white-white, and if the sun is shining, it becomes dazzling white. Why? A snowflake consists of ice and air crystals, the light falling on the rays of the snowflake is reflected from them, scattered and perceived by us as white. And when a sunbeam hits the crystals, it is reflected from it and blinds our eyes.

I decided to conduct experiments to prove that the snow is really white.

2.1 Conducting experiments to answer the question "Why is snow white?"

How I conducted experiments

Experience number 1

I put snow on red cardboard, compared it to a white sheet of paper. Conclusion: Snow is white.

Experience number 2

I took out a transparent plastic bag. I cut it into small pieces. Each piece is a "snowflake". I put all the pieces in a transparent glass. They positioned themselves in different ways.

Result: "snow" in a white glass.

Experience number 3

She poured water into a glass and put it in the freezer. The water turned into transparent ice. Mom broke the ice into small pieces. He turned white.

Conclusion

The pieces of plastic bag and pieces of ice are individually transparent. Light passes through them and is not reflected. When the pieces of the bag and lie chaotically (in different ways, they reflect light in different directions.

Output

Snow is white because each snowflake reflects light in different directions. In scientific language - "light scatters". This makes the snow white.

Each of us has thought about why the snow is white, and not black, blue, red or some other, at least once in our life. Most often, children ask their parents the question "why is snow white", but not even all adults know the answer to this question.

To understand why the snow is of this color, you first need to define the concept of color in general. What is color in terms of physics?

We are surrounded by electromagnetic radiation, which is also called electromagnetic waves.... These waves are everywhere, but most of these waves are invisible to the human eye.

The visible part of electromagnetic radiation is perceived as a color... From the point of view of science, any color is a wave of electromagnetic radiation, which is perceived by human vision and is converted into a color sensation.

The Sun is the primary source of electromagnetic radiation for us. The sun's rays, that is, waves, contain the entire spectrum of visible radiation, that is all basic seven colors - red, orange, yellow, green, blue, blue, purple.

Merging, the colors of the visible spectrum form white.

Some items completely absorb light waves - we see them black, other subjects let the sun go through, that is, are transparent... It is glass, water or ice.

Have you ever read fairy tales about living and dead water? Then you will be interested to know what it really is with their help and much, much more!

Do you know what the density of seawater is equal to and why it is easier to swim in it than in river water? Very interesting information is located, learn new things for yourself!

Most of the objects in our world absorb some of the rays, and some reflect. For example, you can take a regular leaf from a green tree.

What leaf green tells us that from the visible spectrum of solar radiation it reflects rays of green light, and all absorbs the rest.

Orange orange absorbs all rays except orange, red poppy absorbs everything except red, and so on.

We can say the following about snow - it reflects all the rays of the visible spectrum, so we see it white, that is, what the light from the Sun is for us.

Why is the snow white and not transparent? ^

And a little more science. Someone will ask why the snow is still white and not transparent. Snow is essentially water, only in a different state of aggregation.

Water is a liquid, ice is a solid, snow is a loose substance made up of individual ice crystals. Water and ice are transparent.

But in fairness, it should be noted that there are no absolutely transparent bodies in nature, like no absolutely black and absolutely white bodies... Even the glass is not completely transparent.

Be that as it may, water or ice has a more or less smooth surface, which affects the passage of sunlight through them.

Passing through the thickness of smooth ice, the rays are not absorbed and practically do not refract, most of them are transmitted, and a smaller part is reflected from the surface.

Snow is very different in its properties from ice, it is loose and not at all smooth.

To study the properties of snow in more detail, just consider a snowflake. Each snowflake is unique and has its own pattern.

But what all snowflakes have in common is that they are not smooth, but consist of many faces, that is, the smallest surfaces located at an angle to each other.

The mass of snow consists of many such snowflakes that attach to each other. Falling on a snowy surface, sunlight is repeatedly refracted and reflected from the edges of the snowflakes.

Ultimately, most of the visible solar radiation is reflected off the snow. Moreover, as already mentioned, the rays of the entire visible spectrum are reflected, so we see the snow as white.

Snow can be compared to crushed glass or diamonds. If we imagine a huge scattering of diamonds, then it will also seem to us white, sparkling.

Perhaps everyone noticed that in the bright sunlight in winter, the surface of the snow sparkles and shimmers with all the colors of the rainbow.

So, this incident sunlight refracts and breaks down into separate spectral colors. Therefore, we see multi-colored sparkles on the white snow.

Do you know what it equals and why it differs from the fresh boiling point?

What is the dew point, how important it is and how it can be calculated read, keep your home cozy!

When the snow melts, a special type of water is formed - melted water. How you can get it at home, how useful it is for health and how it is used, read here:
, it is very interesting!

Snow makes winter white, it seems to hide the darkness and dirt of autumn, therefore it brings so much joy. Children especially love him. For them, snow is one of the main winter fun. Children make fortresses and snowmen out of it, ride on skis and sledges on it, or simply wallow in it for hours without a visible goal. It is no wonder that there comes a moment when the kids begin to ask their parents why the snow is white.

The nature of light and its role

To answer this question comprehensively and easily, adults must have some knowledge of light, color perception and snow. But you need to start with visible light. Everything around is permeated with electromagnetic waves, but people are able to see only a tiny fraction of them. The visible part of the spectrum consists of wavelengths ranging from 550 to 630 nanometers.

Anything outside this narrow spectrum remains invisible to the human eye. True, waves can be felt by other senses, for example, ultraviolet light cannot be seen, but it warms the skin and can even burn it if you spend a long time on a sunny beach.

Vision is an invaluable gift of nature, thanks to which people have the opportunity to create a stable picture of life and learn about the world. However, without light, human vision becomes a useless instrument. This can be easily shown to a child by going into a room with no windows, such as a bathroom. While the light is on, objects around are visible, their colors are distinguishable. But as soon as the light goes out, the room plunges into impenetrable darkness, all things and colors cease to exist for sight, until they are again illuminated by the sun, live fire or an electric bulb.

The fact is that each snowflake consists of ice particles, i.e. many ice crystals. Each such crystal has facets (like a precious stone). Sunlight reflects off the crystal edges, making the snow white.

But you ask, how do snowflakes form? Very simple. Particles of water that rise upward in the form of vapor freeze in the atmosphere, turning into transparent and pure crystals. These crystals fly up and down, obeying the movement of air. Moving randomly in the atmosphere, the crystals collide with each other and form snowflakes.

Other small air particles (for example, dust or soil lifted from the ground by the wind) also fall into the snowflakes. Gradually, the snowflakes become heavier and fall to the ground in the form of snow under the force of gravity. Each snowflake can contain from 2 to 200 crystals!

But the most interesting thing is the shape of the snow crystals. They necessarily have the form of a six-pointed star or the shape of a hexagon (although crystals of a different shape are sometimes found). Moreover, each of the six faces is exactly like the others, like twin sisters. And despite the fact that the crystals that make up the snowflakes are so similar to each other, in nature it is almost impossible to find two identical snowflakes. Each of them is unique and unique in its design and shape. Try yourself to carefully examine a few snowflakes, and you will see that this is true!

The first. Snowflakes are 95% air. That is why they fall very slowly, at a speed of 0.9 km / h.

Second. Why is snow white? Just because snow has air in its structure. In this case, all possible rays of light are simply reflected from the border of ice crystals with air and scattered.

Third. There have been cases in history when snow of a different color fell. For example, in Switzerland, black snow fell in 1969, just at Christmas, and in 1955, green snow fell on California.

Fourth. In Antarctica and in the high mountains, pink, purple, red and yellowish-brown snow is found. This is facilitated by creatures that live in the snow and are called snow chlamydomonas.

This is the smallest algae that accumulates the astaxanthin pigment. Pinkish or red snow is often found in the Caucasus Mountains.

If you raise the top layer, then below the snow will be white, ordinary.

Algae begin to change color, or rather bloom, when the temperature rises slightly. If the sun warms the surface of the snow, algae, which were previously numb in the snow, revive, begin an active life, and quickly accumulate pigments. If you melt the snow, then under a microscope you can see how quickly red particles rush in the water - this is the snow Chlamydomonas.

Fifth.When a snowflake falls into the water, it emits a high-frequency sound that is not picked up by humans, but, according to scientists, fish really do not like it.

Sixth. Snow melts under normal conditions at a temperature of 0 degrees Celsius. However, a significant amount of snow can evaporate at sub-zero temperatures, bypassing the transformation into a liquid phase. This process occurs when the sun's rays hit the snow.

Seventh.In the winter season, snow reflects up to 90% of the sun's rays from the Earth's surface, directing them back into space, thereby preventing the Earth from warming up.

Eighth. During a snowfall in 1987 in Fort Coy (Montana, USA), a world record holder snowflake with a diameter of 38 cm was found.

Prepared by Inna BAKANOVA

When writing the article, materials from the book were used

Masaru Emoto "Messages of water, secret codes of ice crystals."

Secrets of the birth of snowflakes

How are snowflakes formed? Why do snowflakes always have the correct crystal structure? The following video will answer these questions.

I would like to draw your attention to the fact that snowflakes form in the high layers of the atmosphere. There, high above the ground, purity and harmony reign, they are not affected by negative human thoughts, therefore all snowflakes are beautiful and unique.

When thinking about winter, a snow-white cover that envelops everything around always appears in the imagination, while rarely anyone thinks about why it is white.

Water droplets in the atmosphere freeze at sub-zero temperatures and turn into ice, falling to the ground in the form of snow. Ice is water in a solid state, in itself it is transparent. Then why is the snow white?

Snowflakes also have no color, but if you look at them through a magnifying glass, you can see that they look like crystals, resembling in their shape a regular hexagon with faces. During a snowfall, it is the edges of the snowflakes that reflect the light rays that give the snow its familiar white color.

On the ground, the snow cover is a collection of snowflakes, located very tightly to each other in a chaotic manner. Together, they reflect light with greater strength, so even at night, when the surface is not illuminated by the sun, we see snow white. The source of light rays at night are the moon, stars, lanterns.

However, the reason for the "whiteness" of the snow cover lies not only in the ability of the edges of ice crystals to reflect the light falling on them, but also on the purity of their surface. The bottom line is that no snowflake can be perfectly transparent. In the atmosphere, water droplets mix with various particles (dust, industrial emissions and other pollutants) that are capable of absorbing non-reflected light rays.

Why does the snow shine?

In this case, the well-known law applies: the angle of incidence is equal to the angle of reflection. Billions of microcrystals in the shape of a regular hexagon absorb the sun's rays, refract them, and then reflect in different directions and at different angles, like "sunbeams". Therefore, we see how the snowflakes sparkle and shimmer in the sun.

Why do snowflakes crunch and squeak underfoot?

Walking in the snow, you can often hear a crunch or creak under your feet. This sound is obtained because the crystals of snowflakes rub against each other under mechanical pressure and break. However, this phenomenon can be observed not always, but only at a certain air temperature.

The fact is that the snow creaks only at temperatures from 2 to 20 degrees below zero, and in different temperature ranges, the creak and crunch are accompanied by a special sound. This is due to the fact that in severe frost the crystals of snowflakes become denser and stronger, and at temperatures of 0 ° C and above, the snow cover loses its strength and begins to melt.

In fact, even the breaking of one small snowflake is accompanied by sound. But this sound is so weak that the human hearing organs simply do not perceive it. While trillions of snowflakes break, the sound becomes much stronger and the person clearly hears the characteristic crackling of snow.