Presentation on the topic "Alcohols" in chemistry in powerpoint format. The presentation for schoolchildren contains 12 slides, where from the point of view of chemistry it is told about alcohols, their physical properties ah, reactions with hydrogen halides.

Fragments from the presentation

From the history

Did you know that back in the IV century. BC e. did people know how to make drinks containing ethyl alcohol? Wine was obtained by fermentation of fruit and berry juices. However, they learned to extract the intoxicating component from it much later. In the XI century. alchemists caught a vapor of a volatile substance that was released when the wine was heated.

Physical properties

• Lower alcohols are liquids that are readily soluble in water, colorless, and odorless.
• Higher alcohols are solids that are not soluble in water.

Feature of physical properties: state of aggregation

• Methyl alcohol (the first representative of the homologous series of alcohols) is a liquid. Maybe he has a large molecular weight? No. Much less than carbon dioxide... Then what is it?
• It turns out that the whole point is in the hydrogen bonds, which are formed between the molecules of alcohols, and do not allow individual molecules to fly away.

Feature of physical properties: solubility in water

• The lower alcohols are soluble in water, the higher ones are insoluble. Why?
• The hydrogen bonds are too weak to hold the alcohol molecule, which has a large insoluble part, between the water molecules.

Feature of physical properties: contraction

• Why, when solving computational problems, they never use volume, but only mass?
• Mix 500 ml of alcohol and 500 ml of water. We get 930 ml of solution. The hydrogen bonds between the molecules of alcohol and water are so great that there is a decrease in the total volume of the solution, its "compression" (from the Latin contraktio - compression).

Are alcohols acids?

• Alcohols react with alkali metals. In this case, the hydrogen atom of the hydroxyl group is replaced by a metal. It looks like acid.
• But the acidic properties of alcohols are too weak, so weak that alcohols have no effect on indicators.

Friendship with the traffic police.

• Are alcohols on friendly terms with the traffic police? But how!
• Have you ever been stopped by a traffic police inspector? Did you breathe into the tube?
• If you are unlucky, then an alcohol oxidation reaction took place, in which the color changed, and you had to pay a fine.

We give water 1

Withdrawal of water - dehydration can be intramolecular if the temperature is more than 140 degrees. This requires a catalyst - concentrated sulfuric acid.

We give water 2

If the temperature is reduced, and the catalyst is left the same, then intermolecular dehydration will take place.

Reaction with hydrogen halides.

This reaction is reversible and requires a catalyst - concentrated sulfuric acid.

To be friends or not to be friends with alcohol.

An interesting question. Alcohol belongs to xenobiotics - substances not contained in human body, but affecting his life. It all depends on the dose.

1. Alcohol Is a nutrient that provides the body with energy. In the Middle Ages, the body received about 25% of its energy from alcohol consumption.
2. Alcohol is a drug that has a disinfectant and antibacterial effect.
3. Alcohol is a poison that disrupts natural biological processes, destroying internal organs and psyche and, if used excessively, leads to death.

The most common knowledge about three states of aggregation: liquid, solid, gaseous, sometimes remember about plasma, less often liquid crystal. Recently, a list of 17 phases of a substance, taken from the famous () Stephen Fry, has spread on the Internet. Therefore, we will tell you more about them, because you should know a little more about matter, if only in order to better understand the processes taking place in the Universe.

The list of aggregate states of matter given below increases from the coldest states to the hottest, and so on. can be continued. At the same time, it should be understood that the degree of compression of the substance and its pressure (with some reservations for such unexplored hypothetical states such as quantum, radial, or weakly symmetric) increase from the gaseous state (No. 11), the most "unclenched", to both sides of the list. a visual graph of the phase transitions of matter is shown.

1. Quantum- the aggregate state of matter, achieved when the temperature drops to absolute zero, as a result of which internal bonds disappear and matter disintegrates into free quarks.

2. Bose-Einstein condensate- the aggregate state of matter, which is based on bosons cooled to temperatures close to absolute zero (less than a millionth of a degree above absolute zero). In such a very cold state, it is enough big number atoms are in their minimum possible quantum states and quantum effects begin to manifest themselves at the macroscopic level. Bose-Einstein condensate (often called "Bose condensate", or simply "back") occurs when you cool one or another chemical element to extremely low temperatures (usually just above absolute zero, minus 273 degrees Celsius, the theoretical temperature at which everything stops moving).
This is where completely strange things begin to happen to the substance. Processes normally only seen at the atomic level now take place on a scale large enough to be observed with the naked eye. For example, if you put the “backing” in a beaker and provide the required temperature, the substance will begin to crawl up the wall and eventually will get out by itself.
Apparently, here we are dealing with a futile attempt by the substance to lower its own energy (which is already at the lowest of all possible levels).
Slowing down the atoms using cooling equipment produces a singular quantum state known as a Bose condensate, or Bose-Einstein condensate. This phenomenon was predicted in 1925 by A. Einstein, as a result of a generalization of the work of S. Bose, where statistical mechanics was built for particles ranging from massless photons to atoms with a mass (Einstein's manuscript, which was considered lost, was discovered in the library of Leiden University in 2005 ). The result of the efforts of Bose and Einstein was the concept of Bose gas obeying Bose-Einstein statistics, which describes the statistical distribution of identical particles with integer spin, called bosons. Bosons, which are, for example, and individual elementary particles - photons, and whole atoms, can be with each other in the same quantum states. Einstein suggested that cooling atoms - bosons to very low temperatures would force them to go (or, in other words, condense) into the lowest possible quantum state. The result of such condensation will be the emergence of a new form of matter.
This transition occurs below the critical temperature, which is for a homogeneous three-dimensional gas consisting of non-interacting particles without any internal degrees of freedom.

3. Fermion condensate- the state of aggregation of a substance, similar to the backing, but differing in structure. When approaching absolute zero, atoms behave differently depending on the magnitude of the proper angular momentum (spin). Bosons have integer spins, while fermions have multiples of 1/2 (1/2, 3/2, 5/2). Fermions obey the Pauli exclusion principle, according to which two fermions cannot have the same quantum state. There is no such prohibition for bosons, and therefore they have the opportunity to exist in one quantum state and thereby form the so-called Bose-Einstein condensate. The formation of this condensate is responsible for the transition to the superconducting state.
Electrons have spin 1/2 and are therefore fermions. They combine into pairs (called Cooper pairs), which then form a Bose condensate.
American scientists have attempted to obtain a kind of molecule from fermion atoms with deep cooling. The difference from real molecules was that there was no chemical bond- they just moved together, in a correlated manner. The bond between atoms turned out to be even stronger than between electrons in Cooper pairs. For the formed pairs of fermions, the total spin is no longer a multiple of 1/2; therefore, they already behave like bosons and can form a Bose condensate with a single quantum state. In the course of the experiment, a gas of potassium-40 atoms was cooled to 300 nanokelvin, while the gas was contained in a so-called optical trap. Then an external magnetic field was imposed, with the help of which it was possible to change the nature of interactions between atoms - instead of a strong repulsion, a strong attraction began to be observed. When analyzing the influence of the magnetic field, it was possible to find its value at which the atoms began to behave like Cooper pairs of electrons. At the next stage of the experiment, scientists propose to obtain the effects of superconductivity for fermion condensate.

4. Superfluid substance- a state in which a substance has virtually no viscosity, and during flow it does not experience friction with a solid surface. The consequence of this is, for example, such an interesting effect as the complete spontaneous "creeping" of superfluid helium from the vessel along its walls against the force of gravity. Of course, there is no violation of the law of conservation of energy. In the absence of friction forces, only gravity, the forces of interatomic interaction between helium and the walls of the vessel and between helium atoms act on helium. So, the forces of interatomic interaction exceed all other forces combined. As a result, helium tends to spread as much as possible over all possible surfaces, and therefore "travels" along the walls of the vessel. In 1938, the Soviet scientist Pyotr Kapitsa proved that helium can exist in a superfluid state.
It is worth noting that many of the unusual properties of helium have been known for quite some time. However, in last years this chemical element "pampers" us with interesting and unexpected effects. So, in 2004, Moses Chan and Eun-Siong Kim from the University of Pennsylvania intrigued scientific world the statement that they were able to obtain a completely new state of helium - a superfluid solid. In this state, some helium atoms in the crystal lattice can flow around others, and thus helium can flow through itself. The "superhardness" effect was theoretically predicted back in 1969. And now in 2004 - as if it was an experimental confirmation. However, later and very interesting experiments showed that not everything is so simple, and, perhaps, such an interpretation of the phenomenon, which was previously taken for the superfluidity of solid helium, is incorrect.
The experiment of scientists led by Humphrey Maris from Brown University in the United States was simple and elegant. Scientists placed a test tube upside down in a closed reservoir of liquid helium. Some of the helium in the test tube and in the reservoir was frozen in such a way that the boundary between liquid and solid inside the test tube was higher than in the reservoir. In other words, in the upper part of the test tube there was liquid helium, in the lower part - solid, it smoothly passed into the solid phase of the reservoir, over which a little liquid helium was poured - lower than the liquid level in the test tube. If liquid helium began to seep through solid, then the level difference would decrease, and then we can talk about solid superfluid helium. And in principle, in three of the 13 experiments, the level difference actually decreased.

5. Superhard substance- an aggregate state in which matter is transparent and can "flow" like a liquid, but in fact it is devoid of viscosity. Such fluids have been known for many years and are called superfluids. The fact is that if the superfluid is stirred, it will circulate almost forever, while the normal liquid will eventually calm down. The first two superfluids were created by the researchers using helium-4 and helium-3. They were cooled to almost absolute zero - to minus 273 degrees Celsius. And from helium-4, American scientists managed to get a superhard body. They compressed the frozen helium by more than 60 times pressure, and then the glass filled with the substance was placed on a rotating disk. At a temperature of 0.175 degrees Celsius, the disk suddenly began to spin more freely, which, according to scientists, indicates that helium has become a superbody.

6. Solid- the aggregate state of matter, characterized by the stability of the form and the nature of the thermal motion of atoms, which perform small vibrations around the equilibrium positions. The stable state of solids is crystalline. Distinguish between solids with ionic, covalent, metallic and other types of bonds between atoms, which determines the variety of their physical properties. Electrical and some other properties of solids are mainly determined by the nature of the movement of the outer electrons of its atoms. According to their electrical properties, solids are divided into dielectrics, semiconductors and metals, according to their magnetic properties - into diamagnets, paramagnets and bodies with an ordered magnetic structure. Research into the properties of solids has united into a large area - solid state physics, the development of which is stimulated by the needs of technology.

7. Amorphous solid- condensed aggregate state of matter, characterized by isotropy of physical properties due to the disordered arrangement of atoms and molecules. In amorphous solids, atoms vibrate around randomly located points. In contrast to the crystalline state, the transition from solid amorphous to liquid occurs gradually. Various substances are in the amorphous state: glasses, resins, plastics, etc.

8. Liquid crystal Is a specific aggregate state of a substance in which it simultaneously exhibits the properties of a crystal and a liquid. Immediately it is necessary to make a reservation that not all substances can be in a liquid crystal state. However, some organic matter possessing complex molecules can form a specific aggregate state - liquid crystal. This state occurs when crystals of some substances melt. When they melt, a liquid crystal phase is formed, which differs from ordinary liquids. This phase exists in the range from the melting point of the crystal to some higher temperature, when heated to which the liquid crystal transforms into an ordinary liquid.
How does a liquid crystal differ from a liquid and an ordinary crystal, and how is it similar to them? Like an ordinary liquid, a liquid crystal is fluid and takes the form of a vessel in which it is placed. In this it differs from the crystals known to all. However, despite this property, which unites it with a liquid, it has a property characteristic of crystals. This is the ordering in space of the molecules that form the crystal. True, this ordering is not as complete as in ordinary crystals, but, nevertheless, it significantly affects the properties of liquid crystals, which distinguishes them from ordinary liquids. Incomplete spatial ordering of the molecules that form a liquid crystal is manifested in the fact that in liquid crystals there is no complete order in the spatial arrangement of the centers of gravity of molecules, although there may be a partial order. This means that they do not have a rigid crystal lattice. Therefore, liquid crystals, like ordinary liquids, have the property of fluidity.
An obligatory property of liquid crystals, bringing them closer to ordinary crystals, is the presence of the order of the spatial orientation of molecules. This order in orientation can manifest itself, for example, in the fact that all long axes of molecules in a liquid crystal sample are oriented in the same way. These molecules must be elongated. In addition to the simplest named ordering of the molecular axes, a more complex orientational order of molecules can be realized in a liquid crystal.
Depending on the type of ordering of the molecular axes, liquid crystals are divided into three types: nematic, smectic, and cholesteric.
Research in the physics of liquid crystals and their applications is currently being carried out on a broad front in all the most developed countries of the world. Domestic research is concentrated in both academic and industrial research institutions and has a long tradition. The works of V.K. Fredericks to V.N. Tsvetkova. In recent years of vigorous study of liquid crystals, Russian researchers have also made a significant contribution to the development of the theory of liquid crystals in general and, in particular, of the optics of liquid crystals. Thus, the works of I.G. Chistyakova, A.P. Kapustina, S.A. Brazovsky, S.A. Pikina, L.M. Blinov and many other Soviet researchers are widely known to the scientific community and serve as the foundation for a number of effective technical applications of liquid crystals.
The existence of liquid crystals was established a very long time ago, namely in 1888, that is, almost a century ago. Although scientists were faced with this state of matter before 1888, it was officially discovered later.
The first to discover liquid crystals was the Austrian botanist Reinitzer. Investigating the new substance he synthesized, cholesteryl benzoate, he found that at a temperature of 145 ° C, the crystals of this substance melt, forming a turbid liquid, strongly scattering light. As the heating continues, upon reaching a temperature of 179 ° C, the liquid clears up, that is, it begins to behave optically like an ordinary liquid, for example water. Cholesteryl benzoate exhibited unexpected properties in a cloudy phase. Examining this phase under a polarizing microscope, Rey-nitzer discovered that it has birefringence. This means that the refractive index of light, that is, the speed of light in this phase, depends on the polarization.

9. Liquid- the state of aggregation of a substance, which combines the features of a solid state (retention of volume, a certain tensile strength) and gaseous (variability of shape). A liquid is characterized by short-range order in the arrangement of particles (molecules, atoms) and a small difference in the kinetic energy of the thermal motion of molecules and their potential interaction energy. The thermal motion of liquid molecules consists of oscillations about equilibrium positions and relatively rare jumps from one equilibrium position to another, which is associated with the fluidity of the liquid.

10. Supercritical fluid(SCF) - the state of aggregation of a substance, in which the difference between the liquid and gas phases disappears. Any substance at a temperature and pressure above the critical point is a supercritical fluid. The properties of a substance in a supercritical state are intermediate between its properties in the gas and liquid phases. So, SCF has a high density, close to a liquid, and a low viscosity, like gases. In this case, the diffusion coefficient has an intermediate value between liquid and gas. Supercritical substances can be used as substitutes for organic solvents in laboratory and industrial processes. Supercritical water and supercritical carbon dioxide have received the greatest interest and distribution in connection with certain properties.
One of the most important properties of the supercritical state is the ability to dissolve substances. By changing the temperature or pressure of the fluid, you can change its properties in a wide range. So, you can get a fluid that is close in properties to either a liquid or a gas. Thus, the dissolving ability of a fluid increases with increasing density (at a constant temperature). Since the density increases with increasing pressure, changing the pressure can affect the dissolving ability of the fluid (at constant temperature). In the case of temperature, the envy of the properties of the fluid is somewhat more complicated - at a constant density, the dissolving ability of the fluid also increases, however, near the critical point, a slight increase in temperature can lead to a sharp drop in density, and, accordingly, in the dissolving ability. Supercritical fluids mix indefinitely with each other, therefore, when the critical point of the mixture is reached, the system will always be single-phase. The approximate critical temperature of a binary mixture can be calculated as the arithmetic mean of the critical parameters of substances Tc (mix) = (mole fraction A) x TcA + (mole fraction B) x TcB.

11. Gaseous- (French gaz, from the Greek chaos - chaos), the state of aggregation of matter, in which kinetic energy the thermal motion of its particles (molecules, atoms, ions) significantly exceeds the potential energy of interactions between them, and therefore the particles move freely, uniformly filling in the absence of external fields the entire volume provided to them.

12. Plasma- (from the Greek. Plasma - sculpted, shaped), the state of matter, which is an ionized gas, in which the concentrations of positive and negative charges are equal (quasineutrality). The vast majority of the substance of the Universe is in the state of plasma: stars, galactic nebulae and the interstellar medium. Plasma exists near the Earth in the form of the solar wind, magnetosphere and ionosphere. High-temperature plasma (T ~ 106 - 108K) from a mixture of deuterium and tritium is being investigated in order to implement controlled thermonuclear fusion... Low-temperature plasma (T Ј 105K) is used in various gas-discharge devices (gas lasers, ion devices, MHD generators, plasmatrons, plasma engines, etc.), as well as in technology (see Plasma metallurgy, Plasma drilling, Plasma technology) ...

13. Degenerate substance- is an intermediate stage between plasma and neutronium. It is observed in white dwarfs, plays important role in the evolution of stars. When atoms are under extremely high temperatures and pressures, they lose their electrons (they go into electron gas). In other words, they are completely ionized (plasma). The pressure of such a gas (plasma) is determined by the pressure of the electrons. If the density is very high, all the particles are forced to approach each other. Electrons can be in states with certain energies, and two electrons cannot have the same energy (unless their spins are opposite). Thus, in a dense gas, all the lower energy levels are filled with electrons. Such a gas is called degenerate. In this state, electrons exhibit degenerate electron pressure, which opposes the forces of gravity.

14. Neutronium- the state of aggregation, into which matter passes at ultrahigh pressure, which is unattainable in the laboratory, but exists inside neutron stars. During the transition to the neutron state, the electrons of a substance interact with protons and turn into neutrons. As a result, the substance in the neutron state consists entirely of neutrons and has a density of the order of the nuclear one. In this case, the temperature of the substance should not be too high (in energy equivalent, no more than a hundred MeV).
With a strong increase in temperature (hundreds of MeV and above), various mesons begin to be produced and annihilated in the neutron state. With a further increase in temperature, deconfinement occurs, and the substance passes into the state of a quark-gluon plasma. It no longer consists of hadrons, but of quarks and gluons that are constantly being born and disappearing.

15. Quark-gluon plasma(chromoplasm) - aggregate state of matter in high energy physics and physics elementary particles, in which hadronic matter passes into a state similar to the state in which electrons and ions are in ordinary plasma.
Usually matter in hadrons is in the so-called colorless ("white") state. That is, quarks of different colors cancel each other out. Ordinary matter has a similar state - when all atoms are electrically neutral, that is,
positive charges in them are compensated by negative ones. At high temperatures, ionization of atoms can occur, while the charges are separated, and the substance becomes, as they say, "quasineutral". That is, the entire cloud of matter as a whole remains neutral, and its individual particles cease to be neutral. Exactly the same, apparently, can happen with hadronic matter - at very high energies, color is released and makes matter "quasi-colorless."
Presumably, the substance of the Universe was in the state of a quark-gluon plasma in the first moments after Big bang... Now quark-gluon plasma can be formed for a short time by collisions of particles of very high energies.
Quark-gluon plasma was obtained experimentally at the RHIC accelerator at Brookhaven National Laboratory in 2005. The maximum plasma temperature of 4 trillion degrees Celsius was obtained there in February 2010.

16. Strange substance- the state of aggregation, in which matter is compressed to the limit values ​​of density, it can exist in the form of a "quark soup". A cubic centimeter of matter in this state will weigh billions of tons; moreover, it will transform any normal substance with which it comes into contact into the same "strange" form with the release of a significant amount of energy.
The energy that can be released during the transformation of the matter of the star's core into "strange matter" will lead to a super-powerful explosion of the "quark nova" - and, according to Leahy and Wyed, it was his astronomers who observed in September 2006.
The process of the formation of this substance began with an ordinary supernova, into which a massive star turned. As a result of the first explosion, a neutron star was formed. But, according to Leahy and Uyed, it did not last long - as its rotation seemed to be slowed down by its own magnetic field, it began to shrink even more, with the formation of a clot of "strange matter", which led to an even more powerful, than in a conventional neutron star flying into the surrounding space at a speed close to the speed of light.

17. Strongly symmetrical substance Is a substance compressed to such an extent that the microparticles inside it are layered on top of each other, and the body itself collapses into black hole... The term "symmetry" is explained as follows: Let's take the aggregate states of matter known to everyone from school - solid, liquid, gaseous. For definiteness, the quality solid matter consider a perfect infinite crystal. It has a certain so-called discrete symmetry with respect to transfer. This means that if you move the crystal lattice by a distance equal to the interval between two atoms, nothing will change in it - the crystal will coincide with itself. If the crystal is melted, then the symmetry of the resulting liquid will be different: it will increase. In the crystal, only points were equivalent, which were distant from each other at certain distances, the so-called nodes of the crystal lattice, in which there were identical atoms.
The liquid is homogeneous throughout its volume, all its points are indistinguishable from one another. This means that a liquid can be displaced at any arbitrary distance (and not only at some discrete, as in a crystal) or rotated at any arbitrary angles (which cannot be done in crystals at all) and it will coincide with itself. The degree of its symmetry is higher. The gas is even more symmetric: the liquid occupies a certain volume in the vessel and asymmetry is observed inside the vessel, where there is liquid, and points where it is not. Gas occupies the entire volume provided to it, and in this sense, all its points are indistinguishable from one another. Yet here it would be more correct to speak not about points, but about small, but macroscopic elements, because there are still differences at the microscopic level. At some points in this moment time has atoms or molecules, while others do not. Symmetry is observed only on average, either over some macroscopic volume parameters, or over time.
But there is still no instant symmetry at the microscopic level. If the substance is compressed very strongly, up to pressures that are unacceptable in everyday life, compress so that the atoms were crushed, their shells penetrated each other, and the nuclei began to touch, symmetry arises at the microscopic level. All nuclei are the same and pressed against each other, not only interatomic, but also internuclear distances are absent, and the substance becomes homogeneous (strange substance).
But there is also a submicroscopic level. Nuclei are made up of protons and neutrons that move inside the nucleus. There is also some space between them. If you continue to squeeze so that the nuclei will be crushed too, the nucleons will be tightly pressed against each other. Then, at the submicroscopic level, symmetry will appear, which is not even inside ordinary nuclei.
From what has been said, one can see a quite definite tendency: the higher the temperature and the higher the pressure, the more symmetrical the substance becomes. Based on these considerations, the substance compressed to the maximum is called strongly symmetric.

18. Weakly symmetric substance- a state opposite to a strongly symmetric substance in its properties, which was present in a very early Universe at a temperature close to the Planck temperature, perhaps 10-12 seconds after the Big Bang, when strong, weak and electromagnetic forces were a single superpower. In this state, matter is compressed to such an extent that its mass is converted into energy, which begins to influence, that is, to expand indefinitely. It is not yet possible to reach energies for the experimental obtaining of superpower and transfer of matter into this phase under terrestrial conditions, although such attempts were made at the Large Hadron Collider in order to study the early universe. Due to the absence of gravitational interaction in the composition of the super-force that forms this substance, the super-force is not sufficiently symmetric in comparison with the supersymmetric force, which contains all 4 types of interactions. Therefore, this state of aggregation has received such a name.

19. Beam matter- this, in fact, is not a substance at all, but energy in its pure form. However, it is this hypothetical state of aggregation that a body will assume when it has reached the speed of light. It can also be obtained by heating the body to the Planck temperature (1032K), that is, by accelerating the molecules of the substance to the speed of light. As follows from the theory of relativity, when a speed of more than 0.99 s is reached, the body's mass begins to grow much faster than during "normal" acceleration, in addition, the body lengthens, heats up, that is, begins to radiate in the infrared spectrum. Upon crossing the threshold of 0.999 s, the body changes dramatically and begins a rapid phase transition up to the ray state. As follows from Einstein's formula, taken in full form, the growing mass of the final substance consists of masses that are separated from the body in the form of thermal, X-ray, optical and other radiation, the energy of each of which is described by the next term in the formula. Thus, a body approaching the speed of light will begin to emit in all spectra, grow in length and slow down in time, thinning to the Planck length, that is, upon reaching the speed c, the body will turn into an infinitely long and thin ray moving at the speed of light and consisting of photons that have no length, and its infinite mass will completely transform into energy. Therefore, such a substance is called ray.

"Alcohols" From history  Did you know that even in the IV century. BC e. did people know how to make drinks containing ethyl alcohol? Wine was obtained by fermentation of fruit and berry juices. However, they learned to extract the intoxicating component from it much later. In the XI century. alchemists caught a vapor of a volatile substance that was released when the wine was heated Definition Alcohols (obsolete alcohols) - organic compounds containing one or more hydroxyl groups (hydroxyl, OH), directly bonded to a carbon atom in a hydrocarbon radical  General formula alcohols СxHy (OH) n General formula of monohydric saturated alcohols СnН2n + 1OH Classification of alcohols According to the number of hydroxyl groups CxHy (OH) n Monohydric alcohols CH3 - CH2 - CH2 OH Dihydric glycols CH3 - CH - CH2 OH OH Trihydric glycerols CH2 - CH - CH2 OH OH OH Classification of alcohols By the nature of the hydrocarbon radical of the radical CxHy (OH) n CxHy (OH) n Limit Limit CH3 CH3 –– CH CH2 CH2 2 –– CH 2 OH OH Unsaturated Unsaturated CH CH2 = CH CH –– CH CH2 2 = 2 OH OH Aromatic Aromatic CH CH2 OH 2 --OH Nomenclature of alcohols Review the table and draw a conclusion about the nomenclature of alcohols NOMENCLATURE AND ISOMERIA When forming the names of alcohols, the (generic) suffix - OL is added to the name of the hydrocarbon corresponding to the alcohol. The numbers after the suffix indicate the position of the hydroxyl group in the main chain: H | H- C - O H | H methanol H H H | 3 | 2 | 1 H- C - C - C -OH | | | H H H propanol-1 H H H | 1 | 2 | 3 H - C - C - C -H | | | H OH H propanol -2 TYPES OF ISOMERIES 1. Position isomerism functional group (propanol – 1 and propanol – 2) 2. Isomerism of the carbon skeleton CH3-CH2-CH2-CH2-OH butanol-1 CH3-CH-CH2-OH | CH3 2-methylpropanol-1 3. Interclass isomerism - alcohols are isomeric to ethers: CH3-CH2-OH ethanol CH3-O-CH3 dimethyl ether Conclusion suffix -ol  For polyhydric alcohols, before the suffix -ol in Greek (-di-, -tri-, ...), the number of hydroxyl groups is indicated  For example: CH3-CH2-OH ethanol Types of alcohol isomerism Structural 1. Carbon chain 2. Positions of the functional group PHYSICAL PROPERTIES  Lower alcohols (C1-C11) -volatile liquids with a pungent odor  Higher alcohols (C12- and higher) solids with a pleasant odor PHYSICAL PROPERTIES Name Formula Pl. g / cm3 tm.C boiling point C Methyl CH3OH 0.792 -97 64 Ethyl C2H5OH 0.790 -114 78 Propyl CH3CH2CH2OH 0.804 -120 92 Isopropyl CH3-CH (OH) -CH3 0.786 -88 82 Butyl CH3CH2CH2CH2OH 0.810 -90 118 Specific physical properties: state of aggregation Methyl alcohol (the first representative of the homologous series of alcohols) is a liquid. Maybe he has a large molecular weight? No. Much less than carbon dioxide. Then what is it? R - O… H - O… H - O H R R Why? CH3 - O ... N - O ... N - O N N CH3 And if the radical is large? СН3 - СН2 - СН2 - СН2 - СН2 - О ... Н - О Н Н Hydrogen bonds are too weak to keep an alcohol molecule, which has a large insoluble part, between water molecules Peculiarity of physical properties: contraction Why, when solving computational problems, they never use volume, but only in mass? Mix 500 ml of alcohol and 500 ml of water. We get 930 ml of solution. The hydrogen bonds between the molecules of alcohol and water are so great that there is a decrease in the total volume of the solution, its “compression” (from the Latin contraktio - compression). Some representatives of alcohols Monohydric alcohol - methanol  Colorless liquid with a boiling point of 64C, a characteristic odor Lighter than water. Burns with a colorless flame.  It is used as a solvent and fuel in internal combustion engines. Methanol is a poison  The toxic effect of methanol is based on damage to the nervous and vascular systems. Ingestion of 5-10 ml of methanol leads to severe poisoning, and 30 ml or more - to death Monohydric alcohol - ethanol Colorless liquid with a characteristic odor and burning taste, boiling point 78C. Lighter than water. Mixes with her in any relationship.  Easily flammable, burns with a weak glowing bluish flame. Friendship with the traffic police Are spirits friends with the traffic police? But how! Have you ever been stopped by a traffic police inspector? Did you breathe into the tube? If you were unlucky, then the alcohol oxidation reaction took place, in which the color changed, and you had to pay a fine 3СН3 - СН2 - ОН + К2Сr2O7 + 4H2SO4  K2SO4 + 7H2O + O Cr2 (SO4) 3 + 3CH3 - CH Be friends or not be friends with alcohol An interesting question. Alcohol refers to xenobiotics - substances not contained in the human body, but affecting its vital functions. It all depends on the dose. 1. Alcohol is a nutrient that provides the body with energy. In the Middle Ages, the body received about 25% of its energy from alcohol consumption; 2. Alcohol is a drug that has a disinfectant and antibacterial effect; 3. Alcohol is a poison that disrupts natural biological processes, destroys internal organs and psyche and, if consumed excessively, leads to death. Use of ethanol  Ethyl alcohol is used in the preparation of various alcoholic beverages;  In medicine, for the preparation of extracts from medicinal plants, as well as for disinfection;  In cosmetics and perfumery, ethanol is a solvent for perfumes and lotions. Harmful effects of ethanol  At the beginning of intoxication, the structures of the cerebral cortex suffer; the activity of the brain centers that control behavior is suppressed: reasonable control over actions is lost, a critical attitude towards oneself decreases. I.P. Pavlov called such a state a "riot of the subcortex" irreversible, and even after prolonged abstinence from the use of alcoholic beverages, they persist. If a person cannot stop, then organic and, therefore, mental deviations from the norm are increasing. Harmful effects of ethanol  Alcohol has an extremely unfavorable effect on the vessels of the brain. At the beginning of intoxication, they expand, the blood flow in them slows down, which leads to congestion in the brain. Then, when, in addition to alcohol, harmful products of its incomplete decay begin to accumulate in the blood, a sharp spasm occurs, vasoconstriction, such dangerous complications as cerebral strokes develop, leading to severe disability and even death. QUESTIONS TO REMOVE 1. 2. 3. 4. 5. 6. 7. 8. There is water in one unsigned vessel, and alcohol in the other. Can you use an indicator to recognize them? Who has the honor of obtaining pure alcohol? Can alcohol be a solid? The molecular weight of methanol is 32, and carbon dioxide is 44. Make a conclusion about the state of aggregation of alcohol. Mixed a liter of alcohol and a liter of water. Determine the volume of the mixture. How to conduct a traffic police inspector? Can anhydrous absolute alcohol give off water? What are xenobiotics and how do they relate to alcohols? ANSWERS 1. 2. 3. 4. 5. 6. 7. 8. You can't. Indicators have no effect on alcohols and their aqueous solutions. Alchemists, of course. Maybe if this alcohol contains 12 carbon atoms or more. A conclusion cannot be drawn from these data. Hydrogen bonds between alcohol molecules at a low molecular weight of these molecules make the boiling point of alcohol abnormally high. The volume of the mixture will not be two liters, but much less, approximately 1 liter - 860 ml. Do not drink when driving. Maybe if you heat it up and add conc. sulfuric acid. Do not be lazy and remember everything that you have heard with alcohols, decide for yourself once and for all what your dose is ……. and is it needed at all ????? Polyhydric alcohol ethylene glycol  Ethylene glycol is a representative of saturated dihydric alcohols - glycols;  The name glycols was given due to the sweet taste of many representatives of the series (Greek "glycos" - sweet);  Ethylene glycol is a syrupy liquid of sweet taste, odorless, poisonous. It is well miscible with water and alcohol, hygroscopic. Application of ethylene glycol  An important property of ethylene glycol is the ability to lower the freezing point of water, from which the substance has found wide application as a component of automobile antifreezes and anti-freezing fluids;  It is used to obtain lavsan (a valuable synthetic fiber) Ethylene glycol is a poison  Doses causing fatal poisoning with ethylene glycol vary widely - from 100 to 600 ml. According to a number of authors, the lethal dose for humans is 50-150 ml. Mortality due to the defeat of ethylene glycol is very high and accounts for more than 60% of all cases of poisoning;  The mechanism of the toxic action of ethylene glycol has not been sufficiently studied to date. Ethylene glycol is rapidly absorbed (including through the pores of the skin) and circulates in the blood unchanged for several hours, reaching its maximum concentration in 2-5 hours. Then its content in the blood gradually decreases, and it is fixed in the tissues Polyhydric alcohol glycerin  Glycerin is a trihydric limiting alcohol. Colorless, viscous, hygroscopic, sweet-tasting liquid. Miscible with water in all respects, good solvent. Reacts with nitric acid to form nitroglycerin. Forms fats and oils with carboxylic acids CH2 - CH - CH2 OH OH OH Use of glycerin  Used in     production explosives nitroglycerin; When processing leather; As a component of some adhesives; In the production of plastics, glycerin is used as a plasticizer; In the production of confectionery and beverages (as a food additive E422) Qualitative reaction to polyhydric alcohols Qualitative reaction to polyhydric alcohols  The reaction to polyhydric alcohols is their interaction with a freshly obtained precipitate of copper (II) hydroxide, which dissolves to form a bright blue-violet solution Assignments Fill in a working card for the lesson;  Answer the test questions;  Solve the crossword puzzle  Worksheet of the lesson "Alcohols"  General formula of alcohols Name the substances:  CH3OH  CH3-CH2-CH2-CH2-OH  CH2 (OH) -CH2 (OH)  Make structural formula propanol-2  What determines the atomicity of alcohol?  List the areas of application of ethanol  What alcohols are used in Food Industry?  What kind of alcohol causes fatal poisoning when 30 ml is ingested?  What substance is used as an anti-freeze liquid?  How to distinguish polyhydric alcohol from monohydric alcohol? Production methods Laboratory  Hydrolysis of haloalkanes: R-CL + NaOH R-OH + NaCL  Hydration of alkenes: CH2 = CH2 + H2O C2H5OH  Hydrogenation of carbonyl compounds Industrial  Methanol synthesis from synthesis gas CO + 2H2 CH3-OH (at elevated pressure, high temperature and zinc oxide catalyst)  Hydration of alkenes  Fermentation of glucose: C6H12O6 2C2H5OH + 2CO2 Chemical properties I. Reactions with breaking the RO – H bond  Alcohols react with alkali and alkaline earth metals, forming salt-like compounds - alcoholates 2СH CH CH OH + 2Na  2СH CH CH ONa + H  2СH CH OH + Сa  (CH CH O) Ca + H  3 2 3 2 2 3 3 2 2 2 2 2  Interaction with organic acids (esterification reaction) leads to the formation of esters. CH COОH + HOC H  CH COОC H (ethyl acetate (ethyl acetate)) + H O 3 2 5 3 2 5 2 II. Reactions with cleavage of the R – OH bond with hydrogen halides: R – OH + HBr  R – Br + H2O III. Oxidation reactions Alcohols burn: 2С3H7ОH + 9O2  6СO2 + 8H2O Under the action of oxidizing agents:  primary alcohols are converted into aldehydes, secondary into ketones IV. Dehydration Proceeds when heated with dehydrating reagents (conc. Н2SO4). 1. Intramolecular dehydration leads to the formation of alkenes CH3 – CH2 – OH  CH2 = CH2 + H2O 2. Intermolecular dehydration gives ethers R-OH + H-O – R  R – O – R (ether) + H2O