Ability to distinguish between soft and hard consonants. Obviously, you don’t need to memorize them, but learn to hear them. And for this, the child needs to be told how exactly these sounds are made - this will greatly facilitate his understanding.

Always soft and always hard consonants

Not all consonants in our language are both hard and soft. First, you need your child to remember those of them that are only hard: Zh, Sh, Ts, and also always soft: Ch, Shch, Y. To do this, you can, for example, make a memorial plaque, where the hard ones will always be drawn above blue bricks, and always soft ones - over green pillows (the choice of color is based on how these sounds are designated in the lower grades).

If a child constantly sees this picture, which you put in his workbook or hang above him, then he will quickly remember these consonants.

How vowels “command” consonants

Then you explain to your child that other consonants can be either soft or hard. But the neighboring letters will help suggest this. If after our consonant there is another consonant, then ours is hard. For example: table. What comes after the C sound? So this is a hard consonant.

Vowel sounds “command” the consonant standing in front what it should be. If these are vowels: A, O, U, E, Y, then there are only hard consonants in front of them. And if it is: I, E, Yu, I, E, then it is soft. The softness of the previous consonant is also indicated by

Educational games

To make it easier for your child to remember this, try playing with him. Invite him to place the outer side of his index finger to the palate and pronounce the syllables containing soft and hard consonants in turn. For example: TA - TYA, NA - NYA. Thanks to this, the child will be able to remember exactly how a consonant sound is produced. He will understand that when a soft consonant is formed, the tongue seems to move forward, and its back rises slightly towards the palate. But when hard consonants are pronounced, this does not happen.

Throw the ball to the child, naming a syllable with a hard consonant, and let him return the ball to you, having already pronounced it with a soft one. For example: LA - LA, LO - LE, LY - LI, etc.

At school, students are asked to distinguish hard and soft consonants using blue and green colors. Blue ones are hard and green ones are soft. Cut out a few red, blue and green squares and have them make a word mosaic. The child will display vowel sounds in red, hard consonants in blue, and soft consonants in green. For this, take small words of one or two syllables: fish, elephant, branch, chalk and so on.

Play the “chain of words” game. You pronounce a word ending with a syllable with a hard or soft consonant, and the child names the next word that begins with this syllable. Remembering to determine out loud which consonant, hard or soft, was in this syllable: winds - fish - bagels - cinema etc.

If you methodically explain to your child the difference between hard and soft consonants, this will help him navigate more easily in the future, when studying many of the features of the spelling of the Russian language. Good luck to you!

What sounds are called consonants?
What does a consonant sound consist of?
What are the different consonant sounds?
How many consonant letters and consonant sounds are there in the Russian alphabet?
Which consonant sounds are always hard and which are always soft?
What letters indicate the softness of a consonant?

Sounds in the pronunciation of which the air encounters an obstacle in the mouth are called consonant sounds. A consonant sound consists of noise and voice or only noise.

Consonant sounds are divided into voiced and unvoiced. Voiced ones consist of noise and voice, deaf ones consist only of noise.

The sounds only consist of noise: [k], [p], [s], [t], [f], [x], [ts], [ch], [sh], [sch]. These are voiceless consonants.

Many consonants form pairs by voicing -deafness: [b] - [p], [c] - [f], [g] - [k], [d] - [t], [s] - [s], [f] - [sh].

To memorize voiced consonants, you can learn the phrase: " THE LION AND THE TOAD HAVE MANY FRIENDS».
See all phrases for memorizing voiced and voiceless consonants.

Deaf consonants are easy to remember by the phrase: " STYOPKA, DO YOU WANT A CHECK?- Ugh!».

Consonant sounds are indicated by letters:

B,IN,G,D,AND,Z,Y,TO,L,M,N,P,R,WITH,T,F,X,C,H,Sh,SCH.

In total, the Russian language has 21 consonants.

Consonants are also hard and soft.

Hard and soft sounds differ in the position of the tongue during pronunciation. When pronouncing soft consonants, the middle back of the tongue is raised towards the hard palate.

Most consonants form pairs of hardness-softness:

The following hard and soft consonant sounds do not form hard-softness pairs:

Solid	[and]	[w]	[ts]
Soft	[h❜]	[sch❜]	[th❜]

Table “Consonant sounds: paired and unpaired, voiced and voiceless, hard and soft” (grades 1-4)

Note: in elementary school, hard consonant sounds are indicated in blue, soft consonant sounds in green, and vowel sounds in red.

Hardness consonants are indicated in writing by vowels A , ABOUT , U , S , E .

Softness consonant sound is indicated in writing by vowels E, Yo, I, Yu, I, as well as the letter b(soft sign).

Compare: nose[nose] - carried[n❜os], corner[corner] - coal[ugal❜].

Unpaired voiced sounds [й❜], [l], [l❜], [m], [m❜] [n], [n❜] [р], [р❜] are called sonorous, which means “sonorous” in Latin.

The sounds [zh], [sh], [ch❜], [sch❜] are called sizzling. They got this name because their pronunciation is similar to hissing.

The sounds [zh], [sh] are unpaired hard hissing sounds.
The sounds [ch❜] and [ш❜] are unpaired soft hissing sounds.

The sounds [c], [s❜], [z], [z❜], [ts] are called whistling.

Consonant can not be stressed or unstressed.

In the Russian language, there are more consonant sounds (36) than consonant letters (21), since one letter can denote paired hard and soft sounds: for example, the letter L (el) denotes the sounds [l] and [l❜].

Attention! A consonant sound can form a syllable only with

All speech sounds are divided into vowels and consonants. In turn, consonants can be divided into hard and soft. This is one of the main characteristics of a consonant sound.

What sounds are called soft

Most schoolchildren have no doubt whether a sound is soft or hard. Usually we distinguish them simply by ear. Indeed, these sounds are heard differently than solid ones. When pronouncing them, the tongue moves slightly forward towards the teeth and are localized in the area of ​​the hard palate. That is why after soft consonants, vowels are most often pronounced, which are also formed in front, next to the teeth.

Paired and unpaired soft consonants

Hard and soft sounds often form pairs. For example, the hard sound [B] corresponds to the soft [B’]. In transcription, softness is indicated by an apostrophe.

We see that in the Russian language there are several unpaired hard sounds and several unpaired soft sounds.

Hard and soft paired consonants can perform a meaningful function. For example, MAL and MYAL, CHALK and MEL. There are many linguistic mysteries based on this.

How are soft sounds indicated in writing?

As a rule, soft consonant sounds in writing can be indicated in different ways.

With a soft sign. However, we must remember that the soft sign only indicates the softness of the paired consonant. If we have a hissing one in front of us, its softness cannot be indicated with a soft sign. Hissing ones are either always hard (in which case they cannot be softened) or always soft (in which case a soft sign is unnecessary in this situation). After sibilants, the soft sign performs a grammatical function, that is, with its help, nouns of the 2nd and 3rd declension are distinguished.

Studying the Russian language already in the 2nd grade, children learn about the dual role of the letters E, E, Yu, Ya. If these letters stand in the field of a paired consonant, they are read E, O, U, A and at the same time indicate the softness of the previous consonant: [L'E ], [L'O], [L'U], [L'A].

Similar to the first case, after sibilants E, Yo, Yu, Ya cannot indicate the softness of the previous consonant, therefore spelling E and Yo after sibilants is difficult and is also learned as a rule and also performs the grammatical function of distinguishing parts of speech. For example, the word “arson” is a noun, and the word “arson” is a verb.

In what cases is it not necessary to indicate softness in writing?

Some soft consonant sounds and combinations are not friendly with a soft sign.

This is an unpaired soft sound [Y’]. A soft sign is never placed in its field.

In the combinations CHK, CHN-NCH, CHV, CHT, SHCHN-NSCH, RSHch, a soft sign is not needed.

It is also not required in combinations ST, CH, ZD, ZN and some others, in which S or Z are softened when pronounced before a soft consonant: verses [S’T’], difference [Z’N’], etc.

After a sibilant, a soft sign usually performs a grammatical function, but can also be dividing: “sews”, “whose”, etc.

Undoubtedly, when parents send a small child to first grade, the child may encounter new and unforeseen difficulties. He receives most of the knowledge from his teacher, but not everything can be assimilated and remain in his head forever. The problem may be that the child is still too young to have time to “grab” everything at once.

Such barriers can be given in many subjects and topics. And no, these are not only exact sciences, such as mathematics and natural history. Russian can also be overwhelming for many children, as it is one of the most difficult languages ​​in the world!

As you know, everything big begins with small things, and children, as a rule, begin to study Russian with sounds, which in turn are classified into soft or hard consonants, stressed consonants and unstressed ones. This topic includes many aspects, the study of which is extremely necessary so that every child can perfectly know the basics of the Russian language.

First of all, for a student to begin to study sounds and their features, he needs to become familiar with the letters, which in their own way are divided into consonants and vowels. You also need to know that there are as many as 33 letters in the alphabet, of which only 21 are consonant sounds in the Russian language, which in pronunciation can give 36 different sound pronunciations.

Consonants are always classified. There are hard and soft consonants, voiceless or voiced, sonorant and noisy, paired or unpaired. At the same time, the voiceless and voiced consonants of the word being defined depend on the pronunciation. They consist of noise and voice. Thus, dull sounds are formed with the help of noise and give only deafness, while the latter are distinguished by the presence of sonority due to the voice.

There are fewer vowel sounds; there are only 10 of them in the alphabet, giving only six sounds. They can be shock or unstressed. When the future first grader has already become familiar with and has mastered this material well, we begin to improve the skill so that the student can easily distinguish a soft consonant sound from a hard one.

At the same time, you need to learn to distinguish using different signs, because simply memorizing does not always help. There are cases when a consonant sound in a word can sound either soft or hard, but there are exceptions. Now let's start learning the rules.

Before what vowel?

Which vowels are soft and which are hard? Let's try to figure it out. The first rule sounds like this: “In the case when a consonant is followed by one of the following vowels - a, o, u, e, s - then the sound will always be hard. And “e, yu, ya, e” always makes consonants soft.” As a result, the last all consonant soft words are given. For example, let’s take the word “mother”.

After the consonant “m” comes the vowel “a”, which makes the sound hard, and in the word “uncle” the sounds “ya - ya” make the consonant “d” soft. If children learn this simple rule and learn to use it, subsequent determination of the softness or hardness of a sound will not be difficult for them.

To reinforce the material “Hard and soft consonant sounds” even better, give children similar exercises that reinforce these rules. We advise you to start with the simplest words.

Two consonants in a row

In the case of subsequent consonants, we figured it out without difficulty, but what to do when two consonants are in a row and how to determine the characteristics of the sound in this case? Another rule applies here. Such cases always mean that the consonant will always be hard. Only soft consonants do not appear in this rule.

• As an example, you can take the word “pen”. After “ch” comes the sound “k”, and the child must understand that “ch” will automatically become a hard sound, since the next “k” is a consonant.
• Take your time when explaining to your child these simple, but important and sometimes confusing rules. Monitor whether the child understands, ask questions and don’t be lazy to explain several times.

Indication of hardness and softness in writing

Traditionally, all sound recordings are made through transcription. So, in transcription, if the sound is soft, we put an apostrophe after it, which looks like a comma on top. Showing: `. For example, take the letter “b”. In the word “lamb” there is a hard sound, its sound recording is as follows: [b], and in the word “white” it is already [b`]. In the word “ice”, only “l” and “d” will be soft. That is, in essence, the child writes the same letter, but it, in turn, has different pronunciations.

In transcriptions and in writing, a similar moment can be indicated differently, that is, in two ways:

1. In the case when soft consonants in Russian appear at the end of a word or before another consonant (in most cases a hard one), softness is indicated by a soft sign, the transcription is an apostrophe. For example, “horse”, “ash”
2. If after a consonant there is a softening vowel (which one, see above in the rule), then it is with its help that the softness of consonant sounds is indicated. For example: “chalk”, “sang”, “luk” - the first sounds are always soft.

It is important to know that you should not ignore the fact that any method of indicating the softness of a sound applies only to those who have a pair in hardness. This means that, for example, in the words “tush” and “mascara” the soft sign in the second case only indicates that the given object/phenomenon/creature belongs to the feminine gender. Similar words are: “pike”, “sew”, “drink”, “thicket”.

Constant hardness and softness of a consonant sound

You need to know that there are sounds that, regardless of position, rule or even exception, do not change their position. These are “zh, sh, ts” - they are always hard, and “ch, shch, th” are invariably soft, where zh, sh, ch, shch are hissing consonant sounds.

But it can be difficult for children to remember this aspect well, and then the parent can easily prepare a reminder in a notebook, which will look something like this: zh, sh, ts, ch`, sch`, й`or just underline the last three letters.

“Soft” words

This can be called words in which all soft consonant sounds are soft. There are a huge number of them. For example: “frost”, “glasses”, “skullcaps”, “fun”, “predators”, “squint” - these are words with soft consonants.

• A very exciting and educational activity not only for the child, but also for the parent, will be the search for similar new words in which all the consonants are soft.
• If you have any difficulties, please contact our help! “Pikes”, “uncle”, “blizzard”, “aunt”, “rulers”, “fives”, “ten”, “lilac”, “dates”, “nannies”, “cherry”, “ten” - words, where all consonants are soft. Also play in reverse: we look for all the consonants in the words that are now hard.

Learning by playing

Some sources and reference books recommend focusing on educational games. That is, a child who is carried away by such an activity does not notice how he grasps and learns difficult material. An example of such a game could be the familiar “Find a Pair”.

All that is necessary is to give the child words with hard sounds, and he must come up with another one in response, but with soft ones. This is how you can easily and naturally learn soft consonant sounds in 1st grade!

Usually, children do not have serious difficulties understanding the difference between vowels and consonants. But we should dwell in more detail on hard and soft consonants.

How to teach children to distinguish between hard and soft consonants

The very first thing you need to teach your child: consonant sounds can be hard and soft, but not letters.

Typical error:
Children confuse sounds and letters. We remember that a sound sounds, and a letter is an icon, it is written. A letter cannot be hard or soft; only a consonant sound can be hard or soft in pronunciation.

Sometimes children can easily learn to distinguish soft and hard sounds by ear.
But it happens that this is difficult, and in this case signs will come to the rescue by which you can distinguish hard sounds from soft ones.

Distinctive features of soft and hard sounds

What sound comes after a consonant:

• If after a consonant there is a vowel a, o, u, e, s, then the consonant is hard.
• If after a consonant there is a vowel and, e, yu, i, then the consonant is soft.

Working on examples:
In the words “mama” and “nora” the consonants are hard, because they are followed by “a” and “o”.
In the words “fly” and “nanny” the consonants are soft because they are followed by “e”, “i”, “ya”.

• If another consonant sounds after a consonant, then the first consonant will be hard.
• There are sounds that can only be hard and sounds that can only be soft, no matter what sound is heard or what letter is written after them.

Always hard sounds - zh, sh, ts.
Always soft - th, h, shch.
A common way to learn these sounds is a simple technique: we write the letters that convey these sounds on a line, and emphasize “th, ch, sch.” The underscore symbolizes the cushion on which the soft sounds sit. The pad is soft, which means the sounds are soft.

Soft sign and hard sign

• If there is a consonant at the end of a word and the letter “b” after it, then the consonant is soft.

This rule is easy to apply if the child sees the written word, but it will not help if the child performs the task by ear.

Movement of the tongue when pronouncing soft and hard sounds

When pronouncing a soft sound, the tongue moves slightly forward, approaching (or touching) the palate with its middle.
When pronouncing hard sounds, the tongue does not move forward.

Table of signs of hard and soft sounds

Solid:

1. Before a, o, y, e, y.
2. At the end of a word before a consonant.
3. F, c, w.

Soft:

1. Before the vowels e, e, i, yu, i.
2. If after a consonant there is a soft sign (dust, measles).
3. Y, h, sch.

A picture or simply a list of thematic words is shown, and the task is given to choose words with soft or hard consonants. For example:

Voiced and voiceless consonants

There are 11 pairs of voiced/voiceless consonants in the Russian language.
The phonetic difference between voiced and voiceless consonants lies in the tension of the vocal cords. Voiceless sounds are pronounced with the help of noise, without straining the ligaments. Voiced sounds are pronounced by voice and are caused by vibration of the vocal cords, because air comes out of the larynx noisily.

Mnemonic technique for memorizing voiceless sounds:
Learn the phrase: “Styopka, do you want some cheek? - Fi! All consonant sounds here are unvoiced.

Examples of tasks for children

Tasks for training the differences between paired consonants can be compiled for each pair according to the following principle (using the example of the D/T pair):

Tasks for distinguishing a pair of consonants G/K

Let's do
Word map better together

Word map. I'm fine

Thank you!

easy in the excerpt:

But it's too much easy explanation.

In direct
sense

In a figurative
sense

It's sustainable
expression

This is different
adjective

Offers with
the word "solid":

• With him without hard hands nowhere.
• solid voice.
• hard
• (All
  offers)

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What (who) is HARD - Map of words and expressions of the Russian language

Let's do
Word map better together

Hello! My name is Lampobot, I am a computer program that helps you do...
Word map. I'm fine
I can count, but I still don’t understand very well how your world works. Help me figure it out!

Thank you! Someday I, too, will learn to distinguish the meanings of words.

In what sense is the adjective used? last in the excerpt:

This means that what I described worked inside you. in the last chapter.

In direct
sense

In a figurative
sense

It's sustainable
expression

This is different
adjective

Offers with
the word "solid":

• firmly
• firmly.
• It's me firmly I know.
• (All
  offers)

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Associations to the word SOLID (dictionary of associations of the Russian language)

all associations
men's/women's

Let's do
Word map better together

Hello! My name is Lampobot, I am a computer program that helps you do...
Word map. I'm fine
I can count, but I still don’t understand very well how your world works. Help me figure it out!

Thank you! Someday I, too, will learn to distinguish the meanings of words.

In what sense is the adjective used? main in the excerpt:

Finally the most main spider.

In direct
sense

In a figurative
sense

It's sustainable
expression

This is different
adjective

The word "hard"
associated with
in words:

Men's associations to the word “hard”:

Women's associations to the word “hard”:

Neutral associations for the word “hard”:

Offers with
the word "solid":

• With him without hard hands nowhere.
• If you read these words out loud, it sounds like you're in charge, solid voice.
• This is since the flood happened: then all the honest people went to sea, and hard There are only cowards and liars left on earth.
• (All
  offers)

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Associations to the word SOLID (dictionary of associations of the Russian language)

all associations
men's/women's

NO ASSOCIATIONS

The word "hard"
associated with
in words:

Let's do
Word map better together

Hello! My name is Lampobot, I am a computer program that helps you do...
Word map. I'm fine
I can count, but I still don’t understand very well how your world works. Help me figure it out!

Thank you! Someday I, too, will learn to distinguish the meanings of words.

In what sense is the adjective used? peaceful in the excerpt:

The house reigned peaceful silence, All that was heard was the hasty creak of a quill pen and the rustle of paper.

In direct
sense

In a figurative
sense

It's sustainable
expression

This is different
adjective

Men's associations to the word “hard”:

NO ASSOCIATIONS

Women's associations to the word “hard”:

NO ASSOCIATIONS

Neutral associations for the word “solid”:

NO ASSOCIATIONS

Offers with
the word "solid":

• I realized that I was in trouble, but firmly I decided that I wouldn’t go into the army anyway.
• You will not be able to cry, you will go towards your goal steadfastly and firmly.
• It's me firmly I know.
• (All
  offers)

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My kids: Games for memory development.

We continue the offer
The adult begins the sentence, and the child must continue it.
For example:
We went into the forest and suddenly...
A strong wind rose, it started to rain and then...
The mouse ran into the hole because...
Today the circus canceled the performance because...
What happens? What happens?
Start the game with words:
Snow can be cold, and water can also be cold, and cold can be... - the child must continue - give at least one answer.
now it's the other way around:
Tea can be hot, but fire can be hot, a radiator can be hot...
Stone can be hard, and bread can also be hard, and yet hard can be...
Or vice versa:
A bunny can be white or gray, fluffy or smooth, nimble, lively or toy. And also... and so on, talk about other objects or living beings.
Can a bunny be gray and nimble at the same time? And at the same time smooth and fluffy? Or both big and small?
Or like this:
What is round?
What is spicy?
What is liquid?
What is long?
What is fluffy?
What is hard?
What is square?
What is fragrant?
What's blue?
What first, what then
There are many card games with such tasks. But you can play this game without cards.
You start the phrase, and let the child continue:
First we eat soup, then...
First leaves appear on the tree, then...
A man goes to bed, and then...

OBJECTS IN THE HOUSE
Preferably a lot of players
We begin to list the objects in the house - first starting with the letter “A” - all players must name 1 object each, then starting with “B”, “C”, etc. Whoever cannot name the item is eliminated. Of course, you need to give some time to think about it (this can be a count from 1 to 10)
Picture for memory development:
Let your child look at this picture for 15 seconds, then have him turn away and answer the following questions:
Questions:
1. Are there bananas on the palm tree?
2. How many houses are there in the picture?
3. What is the facial expression of the emoticon?
4. Are the scissors in the picture open or closed?
5. What color is the pencil?
6. Does each house have pipes drawn?


Questions:
1. Are there pictures in the book?
2. In which direction is the plane flying?
3. How many petals does a flower have?
4. Is there sand at the top of the hourglass?
5. What color is the watch?
6. How many hands does the clock have?
7. Does the plane have a number?
To develop attention.
Name the drawn letters:


Which one is which???
Raya and Alla sisters.
Raya has a dark skirt, a white blouse, a bow with small polka dots, and red shoes.
Alla has a dark skirt, a bow with large polka dots, a white blouse, and pink shoes.

Andrey and Pasha are brothers.
Andrey has blue trousers, a jacket with a zipper, a white shirt, and a blue tie.
Pasha has blue trousers, a jacket with a zipper, a white shirt, and a blue tie.
Arseny drew people from triangles, Yulia - from rectangles, Lena - from circles, Yura - from different figures. Where are the drawings of Yulia and Yura? Help Arseny and Lena correct their mistakes.
The pictures show animals and machines (mechanisms) that replace the work of these animals.
Name the pairs: animal and car (mechanism).

What picture should be in place of the question mark?

Tasks for the development of logic
1. A cat sits in each of the 4 corners of the room. Opposite each of these cats are three cats. How many cats are there in this room?
2. The father has six sons. Every son has a sister. How many children does this father have in total?
3. There are 70 students in two classes. One of these classes has 5 more students than the other. How many students are in each of these classes?
4. There are 3 rabbits in a cage. Three girls asked to give them one rabbit each. Each girl was given a rabbit. And yet there was only one rabbit left in the cage. How did this happen?
5. 6 fishermen ate 6 pike perch in 6 days. How many days will it take 10 fishermen to eat 10 pike perch?
6. There were 40 magpies sitting on one tree. A hunter passed by, shot and killed 6 magpies. How many magpies are left on the tree?
7. The boy and the pig weigh as much as 5 boxes. The piglet weighs as much as 4 cats; 2 cats and a pig weigh as much as 3 boxes. How many cats can balance a boy?
8. Two fathers and two sons divided 3 oranges among themselves so that each got one orange. How could this happen? (hint: grandfather, father and grandson = 2 fathers and 2 sons)
9. A caterpillar crawls from the ground along the stem of a plant whose height is 1 m. During the day it rises by 3 dm, and at night it drops by 2 dm. How many days will it take for the caterpillar to crawl to the top of the plant?
10. There are two buckets with a capacity of 4 and 9 liters. How can you use them to bring exactly 6 liters of water from the river?
11. Some number ends in “2”. If you move the number “2” from the end of the number to the beginning, you get a number that is twice the original. Find this number.
Problems to pay attention to
1. Think and tell me - who will swim across the river faster - ducklings or chickens?
2. Think and tell me - what color is the bun’s hair?
3. Guess the riddle:
There were candies in a pile.
Two mothers, two daughters
Yes, grandmother and granddaughter
They took a piece of candy,
And this bunch was gone.
How many candies were in the pile?
4. 5 birches grew. Each birch tree has 5 large branches. Each branch has 5 small branches. There are 5 apples on each small branch. How many apples are there in total?
5. Think and say - what helps polar bears survive in the desert where there is no water?
6. On what trees do ostriches make their nests?
7. There are 2 apples and 4 pears on the table. How many vegetables are there on the table?
8. Think and say - who growls louder: a tiger or a buffalo?
9. Vanya looked out the window in the morning and said:
- And it turns out there is a very strong wind outside. You need to dress warmer.
How did he guess that there was wind outside? What did he see?
10. 2 girls went into the forest to pick mushrooms, and 2 boys came towards them. How many children go to the forest? (hint: 2 - the rest go back)
11. There were 5 candles burning in the room. A man came in and put out 2 candles. How much is left? (hint: 2 - the rest burned)
12. The log was cut into 4 parts. How many cuts did you make?
13. Read the words and say - which word is extra in each row?
- sofa, chair, wardrobe, kennel, bedside table,
- cloves, chamomile, reeds, lilies, aster,
- boletus, fly agaric, russula, boletus, chanterelle.
14. Think and say - how much earth will be in a hole 1 meter deep, 1 meter long and 1 meter wide?
15. A six-year-old girl had a cat with a short tail. She ate a mouse with a long tail, and the mouse swallowed 2 grains and ate a thin piece of cheese. Tell me, how old was the girl who had the cat?
16. There is a rooster on one bank of the river, and a turkey on the other. There is an island in the middle of the river. Which of these birds will reach the island faster?
17. Tell me how many mushrooms can be grown from 5 seeds?
18. Tell me, who lives in the sea at greater depths: pike, crayfish or trout?
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1. Mom has brothers Nikolai and Victor, sister Margarita, son Oleg and daughter Maria. How many children does mom have in total?
2. Three brothers were walking along the road, with each brother there were two brothers. How many people were walking along the road?
3. My name is Sergey. My sister has only one brother. What is the name of my sister's brother?
4. Three musicians played different pieces of music together for 3 hours. How long did each musician play?
5. The thermometer outside the window shows 5 degrees Celsius. How many degrees does another thermometer hanging nearby show?
6. Igor is shorter than Sasha, but taller than Gena. Who is taller: Sasha or Gena?
7. 3 sparrows and 2 doves were sitting on a branch. One dove and one sparrow flew away. How many sparrows are left on the branch?
8. Masha got up early in the morning and looked out the window. The sun was shining outside. Mashenka exclaimed: “Mommy, it rained heavily at night!”
How did she guess? What did the girl see on the street?
9. Which bird do you think flies faster: an ostrich or a crane?
10. It takes 3 minutes to fry 2 eggs. How many minutes does it take to fry 1 egg?
11. Can you tell what penguins eat in Africa?
12. On a large sofa in a row
Tanina's things are:
Two stockings, Marina doll
And cheerful Pinocchio.
Help Tanya
Count her toys.
13. Tell me what is heavier: a kilogram of strawberries or a kilogram of pears?
14. In sunny weather, the road from home to kindergarten takes 10 minutes. Tell me, how long does it take to get back from kindergarten to home if the sun is covered by clouds?
15. Which word has seven letters “I”?
16. Think and tell me, what mushrooms do hares not eat?
17. You, me, and you and I,
How many of us are there in total, open up?
18. Think and tell me, from what kind of dishes can you not eat anything? (from empty)
19. All guys need to know:
Two plus two, of course...
Everyone in the whole world knows:
Fingers on hand...
Joke problems:
- Two chess players played with each other for two hours. How long did each of them play?
- A goose on two legs weighs 2 kg. How much will he weigh standing on one leg?
- There are 5 branches on the maple. There are 2 apples on each branch. How many apples are there on a maple tree?
- What is heavier than 1 kg of salt or 1 kg of flour?
- There were 4 sparrows sitting on the fence. 2 more sparrows flew to them. Ryzhik the cat jumped onto the fence, he wanted to grab the sparrow. How many sparrows are left sitting on the fence?
- Olya and Katya played together in the park for 4 hours. How much time did each girl spend in the park?
- Three brothers have one sister. how many sisters are there?
- There are five apples in the basket. How to divide them between five boys so that one apple remains in the basket?
Alyosha, Styopa and Semyon wrote tests in mathematics at school.
Semyon received a rating of neither “4” nor “5”, Styopa received neither “3” nor “5”.
What grade did Alyosha get?
What are Stepa and Semyon's grades?
The frog did not sit on a leaf or a flower, the caterpillar did not sit on a flower or a stump. Where did the dragonfly land? What about the frog and the caterpillar?
Kolya, Misha and Sasha competed in skiing. Kolya did not take second or third place. Misha is not the third and not the first. Which boy took which place?
The grandmother knitted mittens, socks and a hat for her three grandchildren. Granny knitted neither mittens nor socks for Tanya, nor a hat or mittens for Sveta. What did grandma knit for Kostya? What about Tanya and Sveta?
Tongue twisters for speech development
Often children have problems with the pronunciation of certain sounds. Tongue twisters are one of the methods for correcting such violations, and children usually like such activities.
Let's start with the most famous tongue twister - about Karl and Clara...
Karl has corals. Clara has a clarinet.
Clara stole corals from Karl, Karl stole a clarinet from Clara.
Karl doesn't have corals, Clara doesn't have a clarinet.

The Greek was driving across the river, he saw the Greek - there was a cancer in the river.
The Greek put his hand in the river,
Cancer by the hand of the Greek!
Three magpies chattered on the slide.
Valerik ate dumplings,
And Valyushka made a cheesecake.
-Tell me about your purchase!
-Which purchase?
-About your purchase, about your purchase, about your purchase!
Grass in the yard, firewood on the grass.
Don't cut wood on the grass in your yard.
Prokhor and Pakhom are riding on horseback.
Prokhor and Pakhom are riding on horseback.
Beavers go into the pine forests.
Beavers are kind, beavers are cheerful.
Your sexton should not try to become our sexton:
Our sexton will over-expose your sexton, over-expose.

Mila's mother washed her with soap.
Mila didn't like soap.
The Christmas tree has pins and needles.
Splitting needles near the Christmas tree.
Our Palkan fell into a trap.
Have you washed the raspberries?
They washed, but did not soap.
Kolya stabs the stakes.
Fields field flight.

Sashka has cones and checkers in his pocket.
Masha sewed for the monkey
A fur coat, a hat and pants.
The cuckoo bought a tub,
I decided to bathe the cuckoo chicks.
Ivashka has a shirt, the shirt has pockets,
The pockets are for the shirt, the shirt is for Ivashka.
There's a tiny midge on the window
The cat deftly catches it with its paw.
A hat and a fur coat - this is our Mishutka.
In seven sleighs, seven Semenovs with mustaches sat down in the sleigh themselves.
Senka and Sanka are carrying Sonya on a sled.
The wasp does not have whiskers, not whiskers, but antennae.
Senka is carrying Sanka and Sonya on a sled. Sledge jump, Senka off his feet, Sonya in the forehead, all in a snowdrift.
Sasha walked along the highway and sucked on a dryer.
Four little black little imps were drawing a drawing in black ink.
The river flows, the stove bakes.
The hedgehog has a hedgehog, the grass snake has a snake.
It's terrible for a beetle to live on a bitch.
Two puppies are nipping cheek to cheek at a brush in the corner.
Tongs and pliers - these are our things.
Funny rhymes for children
At Senya and Sanya's
in the nets there is a catfish with a mustache.
Senya was carrying a cart of hay.
Granny bought beads for Marusya.
Mow your hair while there is dew.
Down with the dew
and we're home.
Tso-tso-tso, tso-tso-tso,
tree, ring, porch.
Swans with their cubs were flying.
Little chatterbox
milk chatted and chatted,
didn't blurt it out.
Good pie
curd inside.
From the clatter of hooves, dust flies across the field.
A weaver weaves fabrics for Tanya scarves.
On a black night, a black cat jumped into a black chimney.
Brit Klim is a brother, Ignat is a brother, and brother Pankrat is bearded.
The Christmas tree has pins and needles.
Senka is carrying Sanka and Sonya on a sled.
Sledge jump, Senka off his feet, Sonya in the forehead, all in a snowdrift.
To train your tongue, you can play these games - you can start playing as early as 1.6 years old.
The baby should try to pronounce the highlighted words with you:
A cow was grazing in the meadow - Moo-oo, moo-oo
The striped bumblebee flew - Z-z-z, z-z-z
The summer breeze blew - F-f-f, f-f-f
The bell rang - ding, ding, ding
A grasshopper chirped in the grass - Tr-r-r, tsk-ss-s
A prickly hedgehog ran through - Ph-ph-ph
The little bird sang Till-l, Till-l
And the angry beetle buzzed - J-zh-zh, zh-zh-zh
Tongue exercises are very useful - you can also start at one and a half years old.
First, do this exercise yourself, the baby just watches, and then try it together.
* * * * *
The tongue is about to take a walk:
(open mouth)
He washed his face
(use the tip of your tongue to quickly run over your upper teeth)
I combed my hair,
(run your tongue between the upper and lower teeth several times, stick it forward and hide it back)
He looked around at the passers-by,
run your tongue across your lips - “lick”)
Turned right, left,
(turn the tongue in the indicated direction)
I fell down, I climbed up,
(lower your tongue down and lift it up)
Once - and disappeared in his mouth.
(hide tongue in mouth
Articulation gymnastics.
Several exercises that prepare the tongue for the correct pronunciation of sounds.
1. Make faces.
The child performs various facial movements: puffs out his cheeks, shows his tongue, stretches out his lips like a tube, opens his mouth wide, etc.
2. Clicking your tongue with your mouth wide open.
3. Clicking your tongue, lips stretched into a wide smile.
4. Whistling, with the lips extended into a tube.
Then the child is asked to click twice, click twice, and whistle twice several times in a row.
5. Licking lips, teeth, plates or lollipops.
6. Moving the tongue - in different directions, arching the tongue, clenching and unclenching the tongue, rolling it into a tube, teasing.
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Speech development
Who's doing what? The hen cackles, and the rooster? - Rooster….
The cat meows, and the dog? - Dog….
The crow croaks, and the cuckoo? - Cuckoo...
The cow moos, and the horse? - Horse….
The goose cackles, and the frog? - Frog….
The train is moving, but what about the plane? - Airplane….
The beetle is buzzing, but what about the mosquito? - Mosquito...
the snow creaks, and the paper? - Paper….
a pig grunts, but a sheep? - Sheep...
The duck quacks, and the sparrow? - Sparrow….
A butterfly flies, but a snake? - Snake….
Another lesson on speech development.
Name the small objects. A watch is a watch.
Book - ….
Bed - ….
Cup - ….
Boots - ….
Stick - ….
Sister - ….
Meadow -….
Face - ….
Carpet - ….
Mirror - ….
Complete the sentences: Alyosha has one candy, and Valya has five...
There were three bears in the circus, but now there are six...
I first sewed two buttons, and then five more...
One kitten has two ears, and three kittens have six….
VICE VERSA
Name words that have opposite meanings.
DAY - ….
MORNING - ….
JOY - ….
HEAT -….
LAUGHTER - ….
UP - ….
Descent - ….
SUNRISE - ….
BRAVE - ….
SLOWLY - ….
LONG - ….
SILLY - ….
LIGHT - ….
OLD - ….
HIGH - ….
SICK - ….
THICK - ….
HOT - ….
BRAVE - ….
WIDE - ….
KIND - ….
Help me write a poem:
I will say a word highly,
and you will answer...
I'll say the word far away
and you will answer...
I'll tell you the word coward,
you will answer...
now I’ll say the beginning, - well, answer...!

Complete the sentences:
Winter, spring, autumn, summer are ... (seasons)
Monday, Tuesday, Wednesday are...(days of the week)
January, February, March are...
Morning, day, evening, night - this is...
A doctor, a teacher, a builder - this is...
Swimming, football, gymnastics are...
Square, circle, oval - this is...
Perch, ruff, crucian carp are...
Bullfinch, tit, sparrow - this is...
Poplar, oak, aspen - this is...
Tatiana, Maria, Anna - this is...
Andrey, Ivan, Mikhail are...
Russia, France, Germany - this is...
Volga, Dnieper, Yenisei - this is...
Find the extra concept in each group:
- pen, notebook, brush, pencil.
- engineer, hairdresser, swimmer, teacher.
- kefir, cheese, sour cream, sausage.
- face, forehead, cheeks, nose.
- grandmother, son, dad, boy.
- wind, rain, spring, snow.
- pine, clove, birch, oak.
- river, boat, lake, sea.
- clown, magician, cashier, trainer.
- long, short, tall, new.
- red, small, white, green.
- bright, kind, cheerful, smart.
- count, write, play, read.
- sleep, jump, run, jump.

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Meaning of the word SOLID. What is SOLID?

• Tverdaya is a river in Russia, flows in the Oryol district of the Kirov region. The mouth of the river is located 70 km along the left bank of the Moloma River. The length of the river is 21 km.

  The source of the river is in the spurs of the Northern Uvaly north of the village of Klenovitsa (Shadrichevskoye rural settlement) 30 km northwest of the city of Orlov. The river flows through an uninhabited forest to the southwest and west, flowing into Moloma just below the village of Spasskoye (Spasskoye rural settlement). It has no large tributaries.

There are three main states of matter - gaseous, liquid and solid. In physics, these states are called aggregate states. So, state of matter called a physical state that directly depends on such basic characteristics as pressure and temperature.

Being in one state or another, substances are characterized by various structures. In addition to the listed three main states of aggregation, there are others, but we will not delve into them within the framework of the article.

Influence of particle motion energy on the properties of aggregative states of substances

As you know, any substance consists of molecules, which in turn are divided into atoms. In addition to molecules, ions into which atoms or their groups are converted can also be considered as particles. In fact, ions or molecules have a complex structure, but to simplify their construction and create visual clarity, they are represented in a spherical form.

In absolutely all substances, the force of mutual attraction between their particles prevents their movement relative to each other. However, as the temperature rises, the kinetic energy of the particles begins to increase, thereby creating more and more resistance to the force of attraction between the particles. The state of aggregation of a substance depends on the ratio of the acquired kinetic energy of the particle to the force of their mutual attraction.

Simply put, the current physical state of a substance depends on how freely molecules can continue to “walk” relative to others. By changing the temperature and pressure indicators, you can observe the transition from one state to another.

The most common example of a transition from one state to another in life can be observed in the three states of a water molecule: solid as ice at temperatures below 0 0 C, liquid at temperatures above 0 0 C and gaseous steam, which is formed after water boils at a temperature of 100 0 C and above.

This graph shows how the energy of particles of matter changes in solid, liquid and gaseous states. The greater the energy, the faster the particles move or oscillate. A small proportion of particles have very low or very high energy.

Solid state of aggregation

Due to the strong mutual attraction, the particles do not have the opportunity to develop the necessary kinetic energy and thereby move freely from a given position, provided that the current temperature and pressure are maintained. Particles of solids are located close to each other and form a certain structure, which is called a crystal lattice.

In a solid, the molecules are tightly packed. Typically they form a regular structure called a crystal lattice.

The standard example of a regular crystal lattice is a crystal.

Liquid state of aggregation

A distinctive property of liquids is their fluidity, as a result of which they are able to change their shape. Liquid poured into a vessel instantly takes its shape and, under the influence of the gravitational force of the Earth, is located at its bottom. The boundary of the upper surface of the liquid forms a smooth plane. The kinetic energy of movement of water molecules exceeds their mutual attraction, which in turn is not capable of keeping them in place. The water molecule seems to roll from one to another, creating fluidity visible to our eyes.

Liquid molecules can move freely, just like gas molecules. However, they are “packed” more tightly, which is more like a solid substance.

Liquids, unlike solids, do not have a crystal lattice.

Gaseous state of aggregation

A gaseous substance, like a liquid, fills a vessel, only unlike a liquid, it fills its entire volume. To put it simply, a half-filled liquid into a vessel cannot fill its entire volume, but a gas can. This is achieved due to the very high kinetic energy of gas molecules, which is several times greater than the energy of their mutual attraction, as well as gravitational force. Therefore, the gas does not roll down like a liquid to the bottom of the vessel. Gas, like liquid, does not have a crystal lattice, unlike a solid.

Gas molecules are located at a considerable distance from each other. They move at high speed. The speed is about 300 km/h, colliding with each other and hitting the walls of the vessel in which they are located.

The relative positions between gas molecules change freely, which allows different bodies to pass through its molecules.

Melting point

Physical aggregate states of substances are capable of transitioning from one type to another - from solid to liquid, from liquid to gaseous when their temperature changes. A change in temperature leads to an increase or decrease in kinetic energy. The transition from solid to liquid is called melting.

The boundary of the transition from solid to liquid is set by the so-called melting point with a temperature capable of exciting kinetic energy in the particle, which will be sufficient to separate from its stationary position of the crystal lattice. The higher the temperature, the greater the transferred kinetic energy to the particles of the element. The stronger the force of attraction between particles, the more kinetic energy must be created to release the particles from the crystal lattice.

For example, iron must be heated to 1538 0 C in order for it to begin to melt, and refractory tungsten - to 3422 0 C.

During casting, molten (white-hot) iron is poured into a prepared mold.

At temperatures below 1535 0 C, iron hardens, taking the form of a casting mold.

The melting point of a substance depends on the attractive forces of its constituent particles.

For helium, these forces are so small that it becomes solid at a pressure at least 25 times higher than atmospheric pressure.

Boiling point

Perhaps the most common phenomenon of the transition from a liquid to a gaseous state in everyday life is the boiling of water. While brewing tea, each of us could observe the birth of the process of boiling water. Small bubbles of steam in the thickness of the heated water gradually grow and, reaching critical sizes, begin to rise to the surface, where, bursting, they turn into a gaseous state - steam.

As in the case of melting, there is a limiting temperature, called the boiling point, at which the kinetic energy becomes sufficient to overcome the forces of mutual attraction of particles, which prevent them from breaking away from each other and leaving the occupied volume. Any element of the periodic table or a substance consisting of several elements has its own boiling point. Pure distilled water (H 2 O) has a boiling point of 100 0 C, ethyl alcohol - (-79 0 C), and highly concentrated water boils at a temperature of 338 0 C.

Boiling point also depends on pressure and attractive forces between particles.

At the top of Everest, the boiling point of water is 28 0 C lower than below, above sea level.

However, there are exceptions in which substances can bypass, when transitioning from one state of aggregation to another, an entire transformation phase - going from solid directly to gaseous. This effect is called sublimation or sublimation.

Video selection of experiments with dry ice

An example is the transformation of dry ice (carbon dioxide in solid form immediately into gaseous ice at a temperature of -78.5 0 C.

The influence of pressure and various impurities on boiling or melting

The second factor influencing the state of aggregation of a substance is pressure. By increasing the pressure, the force of pressing one particle of a substance against another increases, and thus it is necessary to apply greater kinetic energy (temperature) to transition from one state to another. The following relationship is formed: the boiling and melting points increase with increasing pressure.

Impurities in the particles of a substance also affect the actual melting or boiling point because they influence the existing forces of attraction between the particles. One striking example of the influence of impurities is scattered salt crystals on ice, which cause the ice to turn into liquid at ambient temperatures below zero.

Under high pressure, potassium acquires strange properties. Then it is solid and liquid at the same time. The researchers are confident that they are dealing with a new state of aggregation.

A group of physicists at the University of Edinburgh has discovered a new state of matter. It was previously thought that matter could be solid, liquid and gaseous, but for the first time, scientists have discovered that it can be in two of these states at the same time.

New state of matter

Physicists led by Andreas Hermann have discovered that potassium metal can be solid and liquid at the same time if extreme pressure and temperature are applied to it. Then the potassium will be solid, but at the same time molten.

It's like holding a sponge filled with water and it starts dripping. And the sponge itself is also made of water!

Physicist Andreas Hermann

Potassium has a pure crystalline lattice structure in the solid state. However, under extreme conditions, strange processes happen to simple metals, such as the conductive metal sodium becoming an insulator under high pressure. Lithium becomes a superconductor at high pressure and low temperature.

Experiments with potassium have shown that at high pressure its atoms organize themselves into a complex arrangement: five tubes of atoms in a square formation, four at the corners and one in the middle, and four chains of atoms interconnected.

When heated, the chains disappear. The researchers called this a chain melting transition, which is thought to occur when potassium chains transition from an ordered to a disordered state.

The developed computer model of 20 thousand potassium atoms showed that at high pressures and temperatures (about 4 GPa), potassium atoms are arranged in the form of interconnected chains and lattices. At the same time, the chemical interactions between the lattice atoms are very strong, so they remain an ordered solid at temperatures up to 550 ° C. But meanwhile, the chains melt into a disordered liquid state. published

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If you have any questions on this topic, ask them to the experts and readers of our project.

Solids are those substances that are capable of forming bodies and have volume. They differ from liquids and gases in their shape. Solids retain their body shape due to the fact that their particles are not able to move freely. They differ in their density, plasticity, electrical conductivity and color. They also have other properties. For example, most of these substances melt during heating, acquiring a liquid state of aggregation. Some of them, when heated, immediately turn into gas (sublimate). But there are also those that decompose into other substances.

Types of solids

All solids are divided into two groups.

1. Amorphous, in which individual particles are arranged randomly. In other words: they do not have a clear (defined) structure. These solids are capable of melting within a certain temperature range. The most common of them include glass and resin.
2. Crystalline, which, in turn, are divided into 4 types: atomic, molecular, ionic, metallic. In them, particles are located only according to a certain pattern, namely at the nodes of the crystal lattice. Its geometry in different substances can vary greatly.

Solid crystalline substances predominate over amorphous substances in their numbers.

Types of Crystalline Solids

In the solid state, almost all substances have a crystalline structure. They are distinguished by their lattices at their nodes containing various particles and chemical elements. It is in accordance with them that they received their names. Each type has characteristic properties:

• In an atomic crystal lattice, particles of a solid are linked by covalent bonds. It is distinguished by its strength. Due to this, such substances have a high boiling point. This type includes quartz and diamond.
• In a molecular crystal lattice, the bonds between particles are characterized by their weakness. Substances of this type are characterized by ease of boiling and melting. They are characterized by volatility, due to which they have a certain smell. Such solids include ice and sugar. The movements of molecules in solids of this type are distinguished by their activity.
• Corresponding particles, charged positively and negatively, alternate at the nodes. They are held together by electrostatic attraction. This type of lattice exists in alkalis, salts. Many substances of this type are easily soluble in water. Due to the fairly strong bond between the ions, they are refractory. Almost all of them are odorless, since they are characterized by non-volatility. Substances with an ionic lattice are unable to conduct electric current because they do not contain free electrons. A typical example of an ionic solid is table salt. This crystal lattice gives it fragility. This is due to the fact that any shift of it can lead to the emergence of ion repulsive forces.
• In a metal crystal lattice, only positively charged chemical ions are present at the nodes. Between them there are free electrons, through which thermal and electrical energy passes perfectly. That is why any metals are distinguished by such a feature as conductivity.

General concepts about solids

Solids and substances are practically the same thing. These terms refer to one of 4 states of aggregation. Solids have a stable shape and a pattern of thermal motion of atoms. Moreover, the latter perform small oscillations near the equilibrium positions. The branch of science that studies the composition and internal structure is called solid state physics. There are other important areas of knowledge dealing with such substances. Changing shape under external influences and movement is called the mechanics of a deformable body.

Due to the different properties of solids, they have found application in various technical devices created by man. Most often, their use was based on properties such as hardness, volume, mass, elasticity, plasticity, and fragility. Modern science makes it possible to use other qualities of solids that can only be detected in laboratory conditions.

What are crystals

Crystals are solids with particles arranged in a certain order. Each has its own structure. Its atoms form a three-dimensional periodic arrangement called a crystal lattice. Solids have different structure symmetries. The crystalline state of a solid is considered stable because it has a minimum amount of potential energy.

The vast majority of solids consist of a huge number of randomly oriented individual grains (crystallites). Such substances are called polycrystalline. These include technical alloys and metals, as well as many rocks. Single natural or synthetic crystals are called monocrystalline.

Most often, such solids are formed from the state of the liquid phase, represented by a melt or solution. Sometimes they are obtained from the gaseous state. This process is called crystallization. Thanks to scientific and technological progress, the procedure for growing (synthesizing) various substances has reached an industrial scale. Most crystals have a natural shape like Their sizes vary greatly. Thus, natural quartz (rock crystal) can weigh up to hundreds of kilograms, and diamonds - up to several grams.

In amorphous solids, atoms are in constant vibration around randomly located points. They retain a certain short-range order, but lack long-range order. This is due to the fact that their molecules are located at a distance that can be compared with their size. The most common example of such a solid in our life is the glassy state. often considered as a liquid with infinitely high viscosity. The time of their crystallization is sometimes so long that it does not appear at all.

It is the above properties of these substances that make them unique. Amorphous solids are considered unstable because they can become crystalline over time.

The molecules and atoms that make up a solid are packed at high density. They practically retain their relative position relative to other particles and are held together due to intermolecular interaction. The distance between the molecules of a solid in different directions is called the crystal lattice parameter. The structure of a substance and its symmetry determine many properties, such as the electronic band, cleavage and optics. When a solid substance is exposed to a sufficiently large force, these qualities can be impaired to one degree or another. In this case, the solid body is subject to residual deformation.

Atoms of solids undergo vibrational movements, which determine their possession of thermal energy. Since they are negligible, they can only be observed under laboratory conditions. of a solid substance greatly affects its properties.

Study of solids

The features, properties of these substances, their qualities and the movement of particles are studied in various subfields of solid state physics.

The following methods are used for research: radio spectroscopy, structural analysis using X-rays and other methods. This is how the mechanical, physical and thermal properties of solids are studied. Hardness, load resistance, tensile strength, phase transformations are studied by materials science. It has a lot in common with solid state physics. There is other important modern science. The study of existing substances and the synthesis of new ones are carried out by solid state chemistry.

Features of solids

The nature of the movement of the outer electrons of the atoms of a solid substance determines many of its properties, for example, electrical ones. There are 5 classes of such bodies. They are set depending on the type of bond between atoms:

• Ionic, the main characteristic of which is the force of electrostatic attraction. Its features: reflection and absorption of light in the infrared region. At low temperatures, ionic bonds have low electrical conductivity. An example of such a substance is the sodium salt of hydrochloric acid (NaCl).
• Covalent, carried out by an electron pair that belongs to both atoms. Such a bond is divided into: single (simple), double and triple. These names indicate the presence of pairs of electrons (1, 2, 3). Double and triple bonds are called multiples. There is another division of this group. Thus, depending on the distribution of electron density, polar and nonpolar bonds are distinguished. The first is formed by different atoms, and the second by identical ones. This solid state of matter, examples of which are diamond (C) and silicon (Si), is distinguished by its density. The hardest crystals belong precisely to the covalent bond.
• Metallic, formed by combining the valence electrons of atoms. As a result, a general electron cloud appears, which shifts under the influence of electrical voltage. A metallic bond forms when the atoms being bonded are large. They are the ones who can donate electrons. In many metals and complex compounds, this bond forms a solid state of matter. Examples: sodium, barium, aluminum, copper, gold. The following non-metallic compounds can be noted: AlCr 2, Ca 2 Cu, Cu 5 Zn 8. Substances with metallic bonds (metals) have varied physical properties. They can be liquid (Hg), soft (Na, K), very hard (W, Nb).
• Molecular, occurring in crystals that are formed by individual molecules of a substance. It is characterized by gaps between molecules with zero electron density. The forces that bind atoms together in such crystals are significant. In this case, the molecules are attracted to each other only by weak intermolecular attraction. That is why the bonds between them are easily destroyed when heated. Connections between atoms are much more difficult to break down. Molecular bonding is divided into orientational, dispersive and inductive. An example of such a substance is solid methane.
• Hydrogen, which occurs between the positively polarized atoms of a molecule or part thereof and the negatively polarized smallest particle of another molecule or part. Such connections include ice.

Properties of solids

What do we know today? Scientists have long studied the properties of the solid state of matter. When it is exposed to temperatures, it also changes. The transition of such a body into liquid is called melting. The transformation of a solid into a gaseous state is called sublimation. As the temperature decreases, the solid crystallizes. Some substances under the influence of cold pass into the amorphous phase. Scientists call this process glass transition.

When the internal structure of solids changes. It acquires the greatest order as the temperature decreases. At atmospheric pressure and temperature T > 0 K, any substances existing in nature solidify. Only helium, which requires a pressure of 24 atm to crystallize, is an exception to this rule.

The solid state of a substance gives it various physical properties. They characterize the specific behavior of bodies under the influence of certain fields and forces. These properties are divided into groups. There are 3 methods of influence, corresponding to 3 types of energy (mechanical, thermal, electromagnetic). Accordingly, there are 3 groups of physical properties of solids:

• Mechanical properties associated with stress and deformation of bodies. According to these criteria, solids are divided into elastic, rheological, strength and technological. At rest, such a body retains its shape, but it can change under the influence of an external force. In this case, its deformation can be plastic (the original form does not return), elastic (returns to its original shape) or destructive (disintegration/breakage occurs when a certain threshold is reached). The response to the applied force is described by elastic moduli. A solid body resists not only compression and tension, but also shear, torsion and bending. The strength of a solid is its ability to resist destruction.
• Thermal, manifested when exposed to thermal fields. One of the most important properties is the melting point at which the body turns into a liquid state. It is observed in crystalline solids. Amorphous bodies have a latent heat of fusion, since their transition to a liquid state occurs gradually with increasing temperature. Upon reaching a certain heat, the amorphous body loses its elasticity and acquires plasticity. This state means it has reached the glass transition temperature. When heated, the solid body deforms. Moreover, it most often expands. Quantitatively, this state is characterized by a certain coefficient. Body temperature affects mechanical characteristics such as fluidity, ductility, hardness and strength.
• Electromagnetic, associated with the impact on solid matter of flows of microparticles and electromagnetic waves of high rigidity. These also include radiation properties.

Zone structure

Solids are also classified according to their so-called zone structure. So, among them there are:

• Conductors characterized in that their conduction and valence bands overlap. In this case, electrons can move between them, receiving the slightest energy. All metals are considered conductors. When a potential difference is applied to such a body, an electric current is formed (due to the free movement of electrons between points with the lowest and highest potential).
• Dielectrics whose zones do not overlap. The interval between them exceeds 4 eV. To conduct electrons from the valence band to the conduction band, large amounts of energy are required. Due to these properties, dielectrics practically do not conduct current.
• Semiconductors characterized by the absence of conduction and valence bands. The interval between them is less than 4 eV. To transfer electrons from the valence band to the conduction band, less energy is required than for dielectrics. Pure (undoped and intrinsic) semiconductors do not pass current well.

The movements of molecules in solids determine their electromagnetic properties.

Other properties

Solids are also classified according to their magnetic properties. There are three groups:

• Diamagnets, the properties of which depend little on temperature or state of aggregation.
• Paramagnets, which are a consequence of the orientation of conduction electrons and magnetic moments of atoms. According to Curie's law, their susceptibility decreases in proportion to temperature. So, at 300 K it is 10 -5.
• Bodies with an ordered magnetic structure, possessing long-range atomic order. Particles with magnetic moments are periodically located at the nodes of their lattice. Such solids and substances are often used in various fields of human activity.

The hardest substances in nature

What are they? The density of solids largely determines their hardness. In recent years, scientists have discovered several materials that claim to be the “strongest body.” The hardest substance is fullerite (a crystal with fullerene molecules), which is approximately 1.5 times harder than diamond. Unfortunately, it is currently only available in extremely small quantities.

Today, the hardest substance that may be used in industry in the future is lonsdaleite (hexagonal diamond). It is 58% harder than diamond. Lonsdaleite is an allotropic modification of carbon. Its crystal lattice is very similar to that of diamond. A cell of lonsdaleite contains 4 atoms, and a diamond - 8. Of the widely used crystals today, diamond remains the hardest.