Why snow is white 5 sentences. Why is snow white

Our Ksyusha became a little bitch. And mom and dad became walking mini-encyclopedias. Therefore, we decided to create the same why-checks to help parents new section“ ” and publish answers to the most common children's questions in it. We will try to adapt all the answers as much as possible for preschool children, so that it is easier for parents to explain the complex laws of nature to them.

It's winter now and that's why, of course, questions about why are in the TOP of why girls :) That's why we publish our answers to the snowiest questions.

What is snow?

Snowflakes are formed in the same way as raindrops: water evaporates from the seas and oceans and rises to the sky, where it cools down and collects into droplets. When it is very cold, water droplets freeze into ice crystals. They fall to the ground in the form of snow. The melted snow evaporates or flows into streams, from where it begins its journey to heaven again.

Why is snow white?

If snowflakes and droplets are of the same nature, then why are droplets transparent and snowflakes white? The fact is that each individual snowflake is transparent in itself, but together they fall to the ground in a chaotic manner and form a loose mass. Snowflakes lie to each other at different angles. Sunlight is reflected first in one snowflake, then in another, and so on, until it is directed back. It turns out that the snow completely reflects the sunlight, and since the rays of the sun white color, then the snow is white. If the rays of our Sun were yellow and red, then the snow would also be yellow or red. At sunset or sunrise, when we see the pink rays of the sun, the snow also turns pink.

Why do snow and ice melt from salt?

Snow and ice are water that freezes (becomes solid) at 0 degrees Celsius. If you add salt to water, you get a saline solution that freezes at temperatures below 0. If you sprinkle salt on ice or snow, we will make them melt, since salt dissolves in water and lowers its freezing point.

First, the ice around the salt crystal will melt, and then the melting process will spread further from this point.

Which snow melts faster?

Melts faster dirty snow, because:

1. There are also salts in the mud, which speed up the process of snow melting.
2. The mud is usually dark, which means that it absorbs the sun's rays and as a result heats up quickly, warming the snow with it.

Can you eat snow?

Snow tends to collect dust on itself. City dust, in addition to the usual natural dirt and bacteria, contains a lot of heavy metals and other toxic substances that are very dangerous for humans. By eating snow, a person absorbs all these toxic substances and exposes his life to the danger of poisoning.

High in the mountains, pure snow falls without dangerous impurities, but such water is also not good for the body, since it lacks the most important salts that are usually found in drinking water. There is only one conclusion: eating snow is not only unhealthy, but also dangerous to health.

Are there identical snowflakes in the world?

More than a hundred years ago, when the first cameras first appeared, one man, nicknamed “Snezhika”, decided to photograph snowflakes under a microscope. He took 5,000 shots, but not a single pattern of snowflakes was repeated. Many years have passed, and scientists are still arguing: are there identical snowflakes. They even created 2 twin snowflakes in their lab, but that still didn't end their argument. Starting another study, scientists came to the conclusion that snowflakes can differ not only in the external pattern, but also internal structure. This means that even if the snowflakes are the same externally, then most likely their internal structure is still different.

Marina Shkerina
Research project "Why is snow white?"

The project was carried out jointly 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 look like white stars. They fall silently to the ground.

I love looking at snowflakes. They are very beautiful. Like lace, everyone is different. Sometimes they stick together and fall to the ground in large flakes. Sometimes a 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, the trees, the roofs of the houses, became white. It was the first snow. I thought: “Why is the snow white?” And I decided to investigate this problem.

This problem allowed us to formulate the research topic: “Why is snow white?”

Having decided on the topic, she set herself the 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 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 that the white color of the snow is due to the reflection of light.

Research methods:

1. Studying the literature on the topic

2. Observation of the object of study

3. Conducting experiments

4. Analysis of the results and conclusions on the study

Chapter I. Theoretical substantiation of experimental work.

1.1 What is snow?

What is snow? This is a lot, a lot of 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”, covered the ground with a white veil. The fallen snow filled up all the pits, ditches, leveled the hillocks - completely transformed the plain. The forest has changed even more. The snow scattered in white tufts over the branches of the trees, covered the leaves and branches that had fallen to the ground with a white blanket, and lay down 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 traces in the snow.

The meaning of the word "snow" I found in "Modern explanatory dictionary". Snow is hard precipitation, consisting of small ice crystals that fall out of clouds at temperatures below 0C. Snow is formed when water vapor in the atmosphere freezes. At first, tiny crystals appear. 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 size of the frozen ice floes is large enough, they begin to sink to the ground. These accumulations of ice floes are what we call snowflakes.

1.2 Where do snowflakes come from?

A snowflake is a frozen water crystal that has the shape of a six-ray 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. It's 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 an ice-crystal 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 was 12 cm in diameter. Typically, snowflakes are about 5 mm in diameter with a mass of 0.004 g.

The crystals that make up snowflakes have a certain shape. This is either a six-pointed star, or a thin plate that has the shape of a hexagon. The fact is that the main water crystal has the shape of a regular hexagon in the plane.

In 1885, American farmer Wilson Bentley took the first successful photograph of a snowflake under a microscope. He has been doing this for 46 years and has taken over 5,000 unique shots. Based on his work, it was proved that there are no two identical snowflakes.

Crystals of various shapes form 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 grapple with each other.

At low temperatures and strong winds, snowflakes collide in the air, crumble and fall to the ground in the form of debris - “diamond dust”.

1.3 Classification of snowflakes.

Prisms- there are both 6-coal plates and thin columns with a 6-coal section. Prisms are tiny and almost invisible to the naked eye. The edges 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 light hairs.

Dendrites- or tree-like, have pronounced branching thin rays. More often these are large crystals, they can be seen with the naked eye. Maximum size dendrite can reach 30 cm in diameter.

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

hollow posts- inside columns with a hexagonal section, it happens that cavities are formed. Interestingly, the shape of the cavities is symmetrical with respect to the center of the crystal. High magnification is needed 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 fused with each other. To get beautiful symmetrical crystals, you need to have a good combination of many weather conditions.

triangular crystals- such snowflakes are formed 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 faces of such rays can grow.

bullet sockets- sometimes during the formation of crystals they can coalesce and increase in random directions. Such formations are easily broken into separate crystals, similar to bullets. Hence the unusual name.

1.4 Why is snow white?

When a Russian person 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 snow that we don’t even think about why snow is white. It turns out that all the colors we perceive depend on the sun's rays. Black objects completely absorb sunlight, and therefore are perceived by us as black. And if the object completely reflects a ray of the sun, then the color will appear white to us.

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

Interesting Facts:

#1: Did you know 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 are tiny bacteria, fungi, and dust in the air that are absorbed by snowflakes as they fall to the earth's surface.

Conclusion on Chapter I

1. I learned that snow is solid atmospheric precipitation, consisting of small ice crystals.

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

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

Chapter II. Organization of experimental work

on the problem "Why is snow white?"

From my observations, 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 shines, it becomes dazzling white. Why? A snowflake consists of ice and air crystals, the light falling on the rays of a snowflake is reflected from them, scattered and perceived by us as white. And when a sunbeam hits the crystals, it reflects from it and blinds our eyes.

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

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

How I did my experiments

Experience #1

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

Experience #2

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

Result: "snow" in a white glass.

Experience #3

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

Conclusion

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

Conclusion

Snow is white because each snowflake reflects light in different directions. Scientific language - "light is scattered." This makes the snow white.

Where does snow come from?

In winter, snow falls from the sky in the form of ice crystals.

Water vapor travels from the ground to the atmosphere, forming clouds. Clouds form throughout the year, regardless of temperature.

Snow is water vapor that freezes into ice crystals in the atmosphere. Sometimes it happens that as many as 200 tiny ice crystals form one snowflake, put together, they form snow.

Why does it snow in winter?

When there is a minimum amount of moisture in the air, and the air temperature drops below freezing (0 degrees Celsius or 32 degrees Fahrenheit) and the ground temperature is steadily below zero, of course, snow falls on the ground: not heavy water drops of rain, but light white snow snow will reach the ground.

Why is snow white?

Snow is virtually colorless. Visible sunlight is white. Most natural materials absorb some spectrum of sunlight, which gives them their color. Because of the absorbency. every thing has its own color. However, snow reflects most of the sunlight. The complex structure of snow crystals results in countless tiny surfaces that effectively reflect visible light. Little sunlight is absorbed by the snow (and is absorbed evenly across the wavelengths of visible light), thus giving the snow its white color.

What shape are snowflake crystals?

Snow comes in different crystalline forms. Often snowflakes are depicted as stellar dentites. However, the snow is various forms: these can be simple prisms, simple triangles, hollow columns, or fern-like twigs-crystals. The shape of a snow crystal is often too small to see with the naked eye. Researchers use a snowflake photomicroscope to document the different shapes and types of snowflakes.
The first person to successfully photograph snowflakes was farmer Wilson Bentley from Vermont (USA). They called him Snowflake Bentley. After several years of experimenting with connecting microscopes to a bellows chamber, in 1885 Wilson Bentley managed to capture the first photograph of a snowflake. In total, he photographed more than 5,000 precious snowflakes.

Snow is a sign of real winter. It is formed when small raindrops freeze. Fluffy white snow is a real miracle. Children make snowmen out of it, play snowballs for them, and build their dwellings for the northern peoples. A thick layer of snow warms the earth. It does not allow frosty air to reach it, and maintains a positive temperature in the depths of the soil.

What is snow and how is it formed?

In scientific terms, snow is a species precipitation. This means that snow falls from the sky in the form of frozen rain. Snow is cold, white and fluffy. It consists of individual snowflakes that look like six-pointed stars. I wonder how snow is formed?

The first condition for the appearance of snow is cold. The temperature at which water turns into ice is 0ºC. When it gets cold outside, the water in puddles and lakes becomes covered with ice (freezes). Rain clouds freeze in the sky at this time. Raindrops turn into snow.

The second way snow is formed is scientifically called evaporation. Hear how it goes. If you wash clothes and hang them outside in winter, the wet sheet will first freeze and become hard. After a few days, the sheet will turn into a soft, dry cloth. What happened? First, the water in the sheet turned to ice. It happened pretty quickly. Then the ice began to evaporate: small microscopic pieces of ice broke off the sheet and rose into the sky. These ice floes were so small that, looking at the drying sheet, we did not notice their flight.

Why is it snowing?

Many small ice floes are found in the heavenly heights. There they gather in a snow cloud. There are so many snowflakes in a cloud that they join together in several pieces. A few small ice stars form a large snowflake, which becomes too heavy and falls down. This is how the snow starts.

In order to form a large snow cloud, one wet sheet is not enough. Many tiny pieces of ice rise into the sky from a frozen lake, puddle or river. There they gather in large snow clouds.

The wind can carry such a cloud far. For example, where there is no frost. Thanks to the wind, snow can fall even in places where lakes and rivers have not yet frozen.

How are snowflakes formed?

Have you ever seen a snowflake under a microscope? It looks like a six pointed star. Each end of the asterisk consists of a white branch on which small white twigs grow.

These branches are scientifically called crystals. They intersect in the middle of the snow star. Each snowflake begins to grow from the center - from the place where the snow branches intersect. The growth of a snowflake is similar to the growth of a tree: six trunks grow from the center, on each of which branches begin to grow. Stars can have different branches (long or short, thick or thin), but always only 6 large branches grow in a snow star.

When water in a river or puddle freezes, ice is formed. The stars in the ice are located close to each other. When the fog or cloud freezes, the stars are located at some distance from each other. If there are too many stars, they are connected in several pieces and fall down. So the snow falls out of the clouds and covers the roads, houses and fields. Falling snowflakes adults call snowfall.

Why does the snow creak underfoot?

If there is a slight frost on the street (-2 or -3 ºС), then there is a lot of water in the fallen snow. They say about such snow that it is “wet”. It is easy to make snowballs and a snowman out of wet snow, to build "fortresses".

When the frost gets stronger (the air temperature drops to -5 or -10 ºC), the snow freezes harder and becomes dry. It is impossible to make a snowman out of dry snow, but it creaks loudly underfoot. Why does dry snow creak?

Each snowflake is like a small star. If we step on the snow, the branches in the icy snowflakes break. So when breaking many snowflakes, a crunch and creak is formed.

Snow creaks with any pressure:

• if it was stepped on;
• went on skis;
• rode on sleds.

Snow stops creaking only when it becomes almost warm (air temperature approaches 0ºC). Or when he was heavily rolled (this happens on the hills, where the snow rolls and turns into ice).

When the snow creaks very loudly?

Snow can squeak louder or quieter. When does the crunch of snow get very loud?

This happens in extreme cold. For example, in the far north at -50ºC, the crunch of snow becomes so loud that it can be heard on the next street.

With warming, when the air temperature approaches 0ºC, the crunch disappears completely. Snowflakes become soft, drops of water appear on their icy branches, which prevents the icy stars from creaking.

Scientists conduct curious experiments with frozen water. It turns out that water hears us and reacts differently to gentle and rude words. That's what the next video is about.

When thinking about winter, a snow-white cover always appears in the imagination, enveloping everything around, and rarely does anyone think about why it is white.

Droplets of water in the atmosphere, at sub-zero temperatures, freeze and turn into ice, falling to the ground in the form of snow. Ice is water in a solid state, it is transparent in itself. Then why is 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 a regular hexagon with edges in their shape. During a snowfall, it is the edges of the snowflakes that reflect the light rays that give the snow its usual white color.

On the ground, snow cover is a cluster of snowflakes located very tightly to each other in a chaotic manner. Together they reflect light with greater force, so even at night, when the surface is not illuminated by the sun, we see snow as 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 faces of ice crystals to reflect the light falling on them, but also in 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 able to absorb unreflected light rays.

Why does snow glitter?

In this case, the well-known law applies: the angle of incidence is equal to the angle of reflection. Billions of microcrystals, having 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 snowflakes sparkle and shimmer in the sun.

Why do snowflakes crunch and creak underfoot?

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

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

In fact, even the break 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 are breaking, the sound becomes much stronger and a person can clearly hear the characteristic crackling of snow.