Topic: Basic provisions of the ICT

New topic questions:

1. MKT

2. Atom

3. Molecule

4. Basic provisions of the ICT

5. Diffusion

6. Brownian motion

7. Relative molecular weight

8. Amount of substance

9. 1 mole

10. Avogadro's number

11. Molar mass

12. Concentration of molecules

MKT

A) Molecular kinetic theory

B) Theory of thermal processes explaining the properties of macroscopic bodies

(Lomonosov M.V.)

Atom

A) The smallest indivisible particle

B) Discovered by Democritus

B) An atom consists of kernels and the surrounding electron cloud.

D) The nucleus of an atom consists of protons and neutrons, and the cloud surrounding it consists of electrons

Molecule

A) Electrically neutral particle

B) Has the basic chemical properties of a substance

B) Consists of atoms connected to each other by chemical bonds

Basic provisions of the ICT

1) All substances consist of particles (atoms and molecules)

2) Particles are in continuous motion

3) Particles interact with each other, i.e. between them there are attractive and repulsive forces

I. All substances are made up of particles

Experiments proving this position:

1. Mechanical crushing

2. Dissolution of a substance

3. Compression and stretching of bodies

Particles

molecules

atoms

electrons

core

protons

neutrons

PARTICLES MOVE CONTINUALLY AND CHAOTICALLY

EXPERIMENTS PROOF THIS POSITION:

• A) DIFFUSION
• B) BROWNIAN MOTION
• C) THE TENDENCY OF GAS TO OCCUPY THE ENTIRE VOLUME

Diffusion

A) Penetration of molecules of one substance into the intermolecular spaces of another substance

B) Diffusion depends on temperature

BROWNIAN MOTION

THERMAL MOTION OF PARTICLES SUSPENDED IN A LIQUID OR GAS OCCURS CHAOTICALLY AND UNLIMITED LONG TIMES

PARTICLES INTERACTING WITH EACH OTHER ARE ATTRACTED AND REPULED

Experiments confirming this position:

• Gluing
• Wetting

Relative molecular mass (RMM)

The ratio of the mass of a molecule to one-twelfth (1/12) of the mass of a carbon atom

• M r – OMM
• m 0 - mass of one molecule
• m 0c – mass of a carbon atom

QUANTITY OF SUBSTANCE

A value showing how many times the number of molecules in a substance is greater than the number of molecules in 12 grams of carbon

ν – amount of substance (mol)

N – number of molecules in a substance

N A – Avogadro's number

M – molar mass (kg/mol)

1 mole

A) The amount of a substance that contains the same number of molecules as are contained in 12 grams of carbon

B) Unit of measurement of the amount of substance

AVOGADRO'S NUMBER

A number showing how many molecules are contained in 1 mole of a substance

N A = 6,02 · 10 23 mole -1

Molar mass

The mass of a substance taken in the amount of one mole

M – molar mass (kg/mol)

m 0 – mass of one molecule

CONCENTRATION

A number showing how many particles are contained in a unit volume of a substance

n – concentration (m -3 )

V – volume (m 3 )

N – number of molecules

Control

1. Which one physical phenomenon based process of salting vegetables, fish, meat? In which case is the process faster?

If Is the brine cold or hot?

• Why does syrup become sweeter over time? taste of fruit?

• Why are sugar and other porous products Can't be stored near odorous substances?

• The smell of a birch broom spreads faster in a hot bath than in a cool room. Why?

• What do you think could happen as a result of a nuclear war?

• How can you explain the disappearance of smoke in the air?

1. OBJECTIVES

• 1. Find the mass of a water molecule if its molecular mass is 18 g/mol.

( m 0 =0,003*10 -23 kg)

• 2. How many molecules are contained in 10 grams of aluminum? M ( Al) = 27 g/mol.

( N =2,2* 10 23 )

2. Testing

on the topic “Basic provisions of the ICT”

• § 4.1, 4.2, summary
• Task:
• What amount of substance is contained in 15 grams of copper if its molar mass is 64 g/mol?

Basic

provisions

The slide reproduces a three-dimensional image of the silicon surface obtained using an atomic force microscope.

MKT

Molecular kinetic theory

• the study of the structure and properties of matter based on the idea of ​​the existence of atoms and molecules as the smallest particles of a chemical substance.
• Leucippus and Democritus - 400 BC.
• M. V. Lomonosov - XVIII century. “The cause of heat and cold”, “On the rotary motion of corpuscles”.

From the poem “On the Nature of Things” by Titus Lucretius Cara, part 1

The principles of things are thus simple and dense,

Being tightly squeezed by the cohesion of the smallest parts,

But not being an accumulation of individual particles,

And distinguished rather by its eternal simplicity.

And nothing can be taken away from them, nor can nature be reduced

It no longer allows it, saving seeds for things.

If not, then nothing less, will

The smallest body is made up of infinite parts:

Half always has their other half,

And there will be no limit to division anywhere.

How then will you distinguish the smallest thing from the universe?

Absolutely, believe me, nothing. Because although there is no

The universe has no end, but even the smallest things

They will consist of infinite parts equally.

Common sense, however, denies that this is to be believed

Maybe our mind, and you have to admit it is inevitable

The existence of that which is completely indivisible, being

Essentially the smallest. And if it exists,

It must be admitted that the original bodies are dense and eternal.

If, finally, everything was nature, creating things,

Forced it to split into small pieces again,

Again, she could never revive anything.

After all, something that does not contain any parts in itself,

There is absolutely nothing that produces matter

You must have: combinations of different weights,

All sorts of movements, shocks, from which things are created.

Atom and molecule

• ATOM –

• MOLECULE - smallest stable particle substances ,

smallest particle chemical element ,

which is the carrier of its chemical properties.

possessing all chemical properties

and consisting of identical (simple substance) or different (complex substance) atoms united by chemical bonds.

It is necessary to clearly distinguish between the concepts of atom and molecule. For example, pure metals do not have a molecular structure: you cannot talk about an “aluminum molecule,” only about an atom (etc.) An atom has the chemical properties of an element, and a molecule has the properties of a substance.

Three main provisions of the ICT:

• All substances - liquid, solid and gaseous - are formed from tiny particles - molecules, which themselves consist of atoms.
• Atoms and molecules are in continuous chaotic motion.
• Particles interact with each other by forces that are electrical in nature.

The importance of atomic-molecular theory

If, as a result of some kind of global catastrophe, all accumulated scientific knowledge would be destroyed, and only one phrase would be passed down to future generations of living beings, what statement, composed of the fewest words, would bring the most information? I believe that this is the atomic hypothesis: All bodies are made of atoms - small bodies that are in continuous motion, attracted at a short distance, but repelled if one of them is pressed more closely to the other. This phrase... contains an incredible amount of information about the world, you just need to apply a little imagination and a little consideration to it.

R. Feynman. Lectures on physics, vol. 1, p. 23

THE IMPORTANCE OF STATISTICAL MECHANICS

• Explanation of natural phenomena: diffusion, surface tension, thermal expansion of bodies, etc.

• Prediction of new material properties.
• Calculations of physical characteristics of bodies: heat capacity, gas pressure, etc.
• Justification of the empirical laws of ideal gas.

STATISTICAL MECHANICS

consisting

from a large number

Brownian motion

Diffusion

Isoprocesses

Diffusion

• the phenomenon of penetration of particles of one substance into the spaces between particles of another.
• The rate of diffusion depends on the temperature and state of the substance (faster in gases).

Role in nature, technology

1. Plant nutrition from the soil.

2. Absorption in humans and animals nutrients occurs through the walls of the digestive organs.

3. The work of the olfactory organs.

4. Cementation.

Mandatory demonstrations: diffusion in gases, liquids, solids Oh. Dependence of diffusion rate on temperature.

Questions for discussing the model: reasons for diffusion, explanation of the dependence of the diffusion rate on the state of aggregation and temperature, possible ways acceleration and deceleration of diffusion.

Trajectory of a Brownian particle.

• Discovered by R. Brown (1827).

• The theory was created by A. Einstein and M. Smoluchowski (1905).

• The theory was experimentally confirmed in the experiments of J. Perrin (1908–1911).

Brownian motion - random movement of small particles suspended in a liquid or gas, occurring under the influence of the thermal movement of molecules.

Brownian particles move under the influence of random collisions of molecules. Due to the chaotic thermal motion of molecules, these impacts never balance each other. It is necessary to clearly show students that the thermal motion of molecules of a substance and Brownian motion are different phenomena.

From the poem “On the Nature of Things” by Titus Lucretius Cara, part 2

So that you better understand that the main bodies ** are restless

Always in perpetual motion, remember that there is no bottom

The universe has nowhere, and the original bodies remain

Nowhere in place, since there is no end or limit to space,

If it is immeasurable and extends in all directions,

As I have already proven in detail on a reasonable basis.

Once this is established, then the primordial bodies, of course,

There is no peace anywhere in the vast emptiness.

On the contrary: constantly driven by different movements,

Some of them fly far away, colliding with each other,

Some of them disperse only for short distances.

Those who have closer mutual cohesion have few

And spinning apart for insignificant distances,

by the complexity of their very figures, being tenaciously entangled,

Powerful roots of stones and bodies form iron

Persistent, just like everything else of this kind,

others, in small numbers, floating in the vast void,

they spin away and run far back

The gap is long. Of these a rare

They provide us with brilliant air and sunlight.

Many, moreover, hover in the vast void

Those that are thrown away from things of combinations and again

They were not yet able to combine with others in movement.

The image of what I have now described and the appearance

This happens before us always and before our eyes.

Look at this: whenever the sunlight comes through

It cuts through the darkness into our homes with its rays,

Many small bodies in the void, you will see, flickering,

They rush back and forth in the radiant glow of light;

As if in an eternal struggle they fight in battles and battles

They suddenly rush into battles in detachments, without knowing peace,

Either converging, or constantly flying apart again.

Can you understand from this how tirelessly

The origins of things are in turmoil in the vast emptiness.

This is how they help to understand great things

Small things, outlining ways to comprehend them.

Boyle's Law - Mariotte The Boyle-Mariotte law states that the product of the absolute pressure of a gas and its specific volume in an isothermal process (at constant temperature) there is a constant value: pv = const . Gay-Lussac's law states that at constant pressure (isobar Gay-Lussac's Law ny process) specific volume of gaseous substance (volume of constant mass of gas) changes directly proportional to the change in absolute temperatures: v 1 /v 2 = T 1 /T 2 . Charles's Law Charles's law, sometimes called Gay-Lussac's second law, states that for a constant specific volume absolute pressures gases change directly proportional to the change in absolute temperatures: p 1 /p 2 = T 1 /T 2 .

Avogadro's law Avogadro's law states that all gases at the same pressure and temperature contain the same number of molecules in equal volumes. From this law it follows that the masses of two equal volumes of different gases with molecular masses μ 1 And μ 2 are equal respectively: M 1 = m 1 N And M 2 = m 2 N , Dalton's law The working fluid used in thermodynamic plants is usually a mixture of several gases. For example, in internal combustion engines, the composition of combustion products, which are the working fluid, includes hydrogen, oxygen, nitrogen, carbon monoxide, carbon dioxide, water vapor and some other gaseous substances. R cm = p 1 + p 2 + p 3 + ... + r n = Σ R i , Mendeleev - Clayperon equation If both sides of the equation of state of an ideal gas (Cliperon equations) multiply by gas mass M , we get the following expression: pvM = MRT ,

Ideal gas equation of state(Sometimes Mendeleev - Clapeyron equation or Clapeyron equation) - a formula establishing the relationship between pressure, molar volume and absolute temperature of an ideal gas. The equation looks like: PVm=RT, where P is pressure, Vm is molar volume, R is the universal gas constant ( R= 8.3144598(48) J ⁄ (mol∙K)) T - absolute temperature, TO.

Gas constant - universal physical constant R, input state equation 1 begging ideal gas: pv = RT(cm. Clapeyron equation) , Where R - pressure, v- volume, T - absolute temperature. G.p. has the physical meaning of the work of expansion of 1 mole of an ideal gas under constant pressure when heated by 1°. On the other hand, the difference in molar heat capacities (See. Heat capacity) at constant pressure and constant volume Wed - c v = R(for all highly rarefied gases). G.p. is usually expressed numerically in the following units: J/deg-mol.. 8.3143 ± 0.0012(1964) erg/deg-mol.. .8,314-10 7 cal/deg-mol.. 1,986 l atm/deg-mol.. 82.05-10 -3 The universal GP, related not to 1 mole, but to 1 molecule, is called the Boltzmann constant (See. Boltzmann constant).

Robert Brown(Brown, Brown) 21.XII.1773–10.VI.1858

• English botanist. Brown's morphological and embryological studies had great importance to build a natural plant system. Discovered the embryo sac in the ovule, established the main difference between angiosperms and gymnosperms; discovered archegonia in the ovules of conifers. For the first time he correctly described the nucleus in plant cells.

• He discovered in 1827 the random movement of small (several micrometers or less in size) particles suspended in a liquid or gas, and described complex zigzag trajectories.

Einstein Albert (14.III.1879–18.IV.1955)

• Theoretical physicist, one of the founders of modern physics. Born in Germany, from 1893 he lived in Switzerland, and in 1933 he emigrated to the USA. Creator of the theory of relativity, the theory of the photoelectric effect, etc. Nobel Prize 1921

In 1905 his first serious scientific work, dedicated to Brownian motion: “On the motion of particles suspended in a fluid at rest, resulting from the molecular kinetic theory.”

Smoluchowski Marian (28.5.1872 – 5.9.1917)

• Polish physicist. Main works on molecular physics and thermodynamics. He theoretically substantiated the phenomenon of a temperature jump at the gas-solid interface, showed the limitations of the classical interpretation of the second law of thermodynamics, established the laws of fluctuations of equilibrium states, etc.

In 1905 - 06 Based on the kinetic law of energy distribution, he created the theory of Brownian motion, which proved the validity of the kinetic theory of heat.

Perrin(Perrin) Jean Baptiste (30.IX.1870–17.IV.1942)

• French physicist. Proved that cathode rays are a stream of charged particles. He studied electrokinetic phenomena and proposed a device for studying electroosmosis (1904). Established the bimolecular structure of thin soap films. Together with his son F. Perrin, he studied the phenomena of fluorescence. Nobel Prize (1926).

Perrin's work on the study of Brownian motion provided experimental confirmation of the Einstein–Smoluchowski theory; they allowed Perrin to obtain a value for Avogadro's number that was in good agreement with the values ​​obtained by other methods, and to finally prove the reality of molecules.

The relative molecular (or atomic) mass of a substance M r is the ratio of the mass of a molecule (or atom) m 0 of a given substance to 1/12 of the mass of a carbon atom m 0C M r (H 2 O) = 2 1 + 16 = 18 (a.u. .m.) Let's calculate M r of water H 2 O (for this we use the periodic table) Mendeleev Atomic unit mass (amu) 1.66 kg

One mole is the amount of a substance that contains the same number of molecules or atoms as there are atoms in carbon weighing 12 g. 1 mole of any substance contains the same number of atoms or molecules. This number of atoms is denoted N A and is called Avogadro’s constant in honor of the Italian scientist (19th century). N A = 6·10 23 mol -1

4. Thus, the gas pressure on the wall: P = = _______ This equation, first derived by the German physicist R. Clausius, is called the basic equation of the molecular kinetic theory of an ideal gas. It establishes a connection between microscopic parameters and macroscopic (measurable) quantities.

Macroscopic parameters include: ___ (________), ___ (_________) Thermal equilibrium is ... Temperature characterizes the degree of ... Temperature is measured using ... Page The Celsius scale (C) is determined by two points: ...

Page Experience: Conclusions: At 0C: ​​At 100C:

Task. Given: Solution: Answer: pcs.

Page Experimental confirmation of the formula: Stern's experiment (1920)

Poll following the lesson: 1. How will the root mean square speed of molecules change when the temperature increases by 4 times? 2. Which molecules in the atmosphere move faster: nitrogen or oxygen molecules? Why? 3. What is absolute zero on the Celsius scale? 4. How are the volume, pressure and number of molecules of various gases related at thermal equilibrium?

Corollary: - Clapeyron equation R – universal gas constant Problem, 928

Physical dictation Option 1 Option 2

Dynamic equilibrium is a state in which _______ Saturated steam - steam, _______ The concentration of ________ saturated _____ at a constant ________ does not depend on its ____ Since p=nkT, the pressure of ________ steam _____________ on the volume it occupies. Saturated vapor pressure (p vp) is the vapor pressure at which ______ is in equilibrium with its _________.

Critical temperature is the maximum _____ at which _____ will turn into __ P n.a. at 100C equals Pa (760 mmHg) Mixture pressure: Components

Evaporation. Condensation. Boiling. Vaporization is the phenomenon of turning a liquid into vapor. I. - vaporization from the surface of a liquid, accompanied by the absorption of energy. Depends on: Temperature (tC - I.) Surface area of ​​the liquid Type of liquid K. - vaporization throughout the entire volume of the liquid at a certain tC (boiling point). During boiling, the temperature does not change! (t=const)

During evaporation, only fast molecules that are able to overcome the attraction of other molecules fly out, and the temperature decreases (tC). boiling point depends on pressure environment and the presence of impurities. Inside the bubble is saturated steam, i.e. pressure Psteam = Water. t P steam V bubble Fa floats up Examples: “Blowing on tea”, “it’s cold when wet.” Examples: “Salt is added after boiling,” “in the mountains, water boils at 80 C.”

§Air humidity Why know about it? Books Fabrics Products Electrical appliances, etc. Air humidity is the content of water vapor in the atmosphere. In 1 year, billions of tons of water evaporate from the Earth's surface! Partial pressure of water P is the pressure produced by water vapor in the total atmospheric pressure.

Absolute humidity– the amount of water vapor per unit volume (water vapor density) Relative humidity – the ratio of absolute. humidity ρ to the density ρ 0 of saturated steam at a given temperature, expressed in %. P – partial pressure P 0 – saturated vapor pressure. P 0 and ρ 0 are found from the table

"Mono" - one. A monocrystal is a solid body whose particles form a single crystal lattice. An example of single crystals is the widespread hexagonal quartz crystals. Crystals of diamond, tourmaline, etc. are less common. They all have the characteristic shape of polyhedra h ttp:// /…

Anisotropy-dependence physical properties substances from the direction In plane A there are many particles, they are located close to each other, there is a strong interaction. In plane B there are fewer particles, the distance between them is greater; the particles of the plane interact with each other weakly

Graphite and diamond are made of carbon...

Sapphire (corundum) contains impurities of titanium and iron. Microcircuits are formed on sapphires.

Second only to diamond among natural minerals, sapphire has an exceptionally high hardness - 9 points on the hardness scale out of a possible 10. Using sapphire powders you can drill, polish, sharpen stone and metal

Diamond is the hardest creation of nature. About 80% of all mined diamonds are used in industry.

Due to their hardness, diamonds are used for processing super-hard materials, exploration and mining. Before 1430, diamonds were not used as jewelry. The trendsetter for them was the Frenchwoman Agnes Sorel. ...

Among precious stones, ruby ​​ranks second in strength after diamond. Some examples of ruby, distinguished by their particular purity of color, are valued even more than diamonds of the same weight...

Due to its high hardness, ruby ​​is widely used in industry. Using ruby, you can produce an intense red beam of light millions of times brighter than the sun. Ruby lasers are used in scientific research for atmospheric sounding...

Emerald crystal Color depends on the content of chromium oxide ... ...

Deposits of emeralds are few in number. IN ancient world mining was carried out only in Egypt. One of the best in our time is considered to be the mines in the Copi Mountains in the mountains of Colombia, which the Spanish conquerors captured in the 16th century. ...

A polycrystal is a solid body consisting of randomly oriented single crystals... In nature, randomly fused single crystals are more common. Examples of polycrystals are: rock salt (Fig. 1), quartz (Fig. 2), sugar, ice, iron, copper.

Among the bodies that are generally considered solid because they retain their shape and volume and have strength, there are also those that differ significantly from crystals. The particles in them are arranged in the same disorder as in a liquid. Amorphous bodies include glass, resin, rosin, and plastics. ...

CrystalsAmorphous bodies Particles are arranged in an orderly, strictly defined manner. There is no order in the arrangement of particles. Particles make “jumps” Melting at a certain temperature Do not have a specific melting point AnisotropicIsotropic Have a characteristic polyhedron shape Do not have the correct cut

Liquid crystals are substances that simultaneously have the properties of both liquids (fluidity) and crystals (anisotropy). In structure, they are liquids similar to jelly, consisting of elongated molecules, ordered in a certain way throughout the entire volume of this liquid. The external state of liquid crystals when heated can change from solid to liquid crystalline and completely transform into liquid form with a further increase in temperature.

Application of liquid crystals By selecting the composition of a liquid crystal substance, indicators are created for different temperature ranges and for various designs. For example, a liquid crystal indicator on a patient’s skin quickly diagnoses hidden inflammation and even a tumor. Liquid crystals are used to detect vapors of harmful chemical compounds and gamma and ultraviolet radiation hazardous to human health. Pressure meters and ultrasound detectors have been created based on liquid crystals. But the most promising area of ​​application of liquid crystalline substances is information technology. Currently, color LCD screens are used in cell phones, monitors and televisions. They have small thickness, low power consumption, high resolution and brightness. ...

The world's first mineralogical reserve was created on the initiative of V. I. Vernadsky, H. M. Fedorovsky and A. E. Fersman in the Urals (in the Ilmen Mountains, near the city of Miass) in the early years Soviet power …

The area of ​​the reserve is 303.7 km². The length of the Ilmen ridge from north to south is 41 km. The highest peak is Mount Ilmentau (747.3 m). The hydrological network of the Reserve makes up 9% of the territory. There are 30 lakes in the reserve. deep lake Bolshoi Kisegach 34 m The longest river Bolshaya Cheremshanka 9.8 km Minerals, rocks Minerals 264 First discovered in the world in Ilmeny 16 Rocks over 70 Mines over 400

Russia, year 1842, October 8. At the Tsarevo-Aleksandrovsky mine near the city of Miass, which is Southern Urals, a gold nugget weighing 36 kg 16 g was found. Nowadays the “Big Triangle” - this is the name of the unique specimen - can be seen in the Diamond Fund of the Moscow Kremlin. It is considered the largest surviving one in the world. How many degrees will it heat up if it receives J of heat? The specific heat capacity of gold is 0.13 kJ/(kg K). Answer: 4 °C. ...

In 1813, on one of the tributaries of the Ural River Iset, where poor gold-bearing quartz veins were being mined, a young girl, Katya Bogdanova, found a large nugget of platinum and brought it to the clerk. What is the mass of a platinum nugget found in the Urals in 1904 if it would take J of energy to heat it by 20 °C? The specific heat capacity of platinum is 0.14 kJ/(kg * K). Answer: 8.395 kg.

1.What three types are solids divided into according to the nature of the arrangement of particles? What determines whether solids belong to one of these types? 2.What is the difference between mono- and polycrystals? 3.What bodies are classified as amorphous? 4.Wood is anisotropic. Is it a crystalline body? 5.Would the profession of glassblowing arise if glass were a crystalline body rather than an amorphous one?

1. A glass cube and a cube cut from a quartz single crystal are placed in hot water. Will the cubes keep their shape? 2. A cube cut from a single crystal can turn into a parallelepiped. Why is this possible? 3. You can drop an iron basin ten thousand times, but you cannot drop a porcelain vase even once. After all, ten thousand times you need ten thousand vases. Why? ...

2. From the history of the development of MCT The foundation of MCT is the atomistic hypothesis: all bodies in nature consist of the smallest structural units - atoms and molecules. PeriodScientistTheory 2500 years ago D r. Greece Leucippus, Democritus from Abdera originated in the 18th century. M.V. Lomonosov, an outstanding Russian scientist and encyclopedist, considered thermal phenomena as a result of the movement of particles forming bodies of the 19th century. In the works of European scientists, it was finally formulated

Objectives of the lesson: 1. Formulate the basic principles of molecular kinetic theory (MKT) 2. Reveal the scientific and ideological significance of Brownian motion 3. Establish the nature of the dependence of the forces of attraction and repulsion on the distance between molecules

3. Basic provisions of MCT I. All substances consist of particles Experiments: Mechanical crushing Dissolution of matter Compression and stretching of bodies When heated, bodies expand Electron and ion microscopes Particles molecules atoms electrons nucleus neutrons protons

4. Diffusion Diffusion is the process of mutual penetration of various substances due to the thermal movement of molecules. Diffusion occurs in: gases, liquids, solids. Molecular speed: V gas > V liquid > V solid V liquid > V solid"> V liquid > V solid"> V liquid > V solid" title="4. Diffusion Diffusion is the process of mutual penetration of various substances due to the thermal movement of molecules. Diffusion occurs in: gases, liquids, solids. Speed ​​of movement of molecules: V gas > V liquid > V solid"> title="4. Diffusion Diffusion is the process of mutual penetration of various substances due to the thermal movement of molecules. Diffusion occurs in: gases, liquids, solids. Molecular speed: V gas > V liquid > V solid"> !}

6. Interaction of molecules 1.r 0 = d F pr = F from 2. r 0 d F pr > F from r 0 - the distance between the centers of the particles d - the sum of the radii of the interacting particles d F pr > F from r 0 - the distance between the centers of particles d - the sum of the radii of interacting particles "> d F pr > F from r 0 - the distance between the centers of particles d - the sum of the radii of interacting particles "> d F pr > F from r 0 -distance between the centers of particles d-sum of radii of interacting particles" title="6. Interaction of molecules 1.r 0 = d F pr = F from 2. r 0 d F pr > F from r 0 -distance between centers particles d is the sum of the radii of interacting particles"> title="6. Interaction of molecules 1.r 0 = d F pr = F from 2. r 0 d F pr > F from r 0 - the distance between the centers of the particles d - the sum of the radii of the interacting particles"> !}

7. Control 1. What physical phenomenon is the process of salting vegetables, fish, and meat based on? In which case does the process happen faster - if the brine is cold or hot? 2.What phenomenon is the canning of fruits and vegetables based on? Why does sweet syrup taste like fruit over time? 3.Why should sugar and other porous foods not be stored near odorous substances?