Ethyl alcohol


Properties of alcohols

Getting the alcohols

Ethyl alcohol
Monatomic alcohols Polyatomic alcohols Properties of alcohols Getting the alcohols

Ethyl alcohol
Ethyl alcohol

Метиловый спирт
Formic alcohol (methyl)


Polyatomic alcohol glycerin

ethylene glycol
ethylene glycol
Alcohols - derivatives of hydrocarbons, in which molecules have one or multiple hydroxyl groups OH
All alcohols are divided into monatomic and polyatomic.

Monatomic alcohols

Monatomic alcohols - alcohols that have one hydroxyl group.
There are primary, secondary and tertiary alcohols:
-the primary alcohols have a hydroxyl group near the first carbon atom, the secondary - near the second, etc.
Alcohol reaction
Properties of alcohols, which are isomeric, in many similar, but in some reactions they have differents.
Comparing the relative molecular mass alcohols (Mr) with relative atomic masses of hydrocarbons, it is to notice that the alcohols have a higher boiling point. This is due to the hydrogen bonding between the H atom in the group OH of one molecule and the O atom in the group OH other molecules.
Upon dissolution of the alcohol in the water the hydrogen bonds are formed between molecules of alcohol and water. This explains the decrease of the volume of the solution (it will always be less than the sum of the volumes of water and alcohol separately).
The most prominent representative of the chemical compounds of this class is ethanol. Its chemical formula is C2H5-OH. Concentrated ethanol (wine alcohol or ethanol) is prepared from dilute solutions by distillation. It is intoxicating, and in large dose is a poison which destroys living tissue the liver and brain.
It should be noted that ethanol is useful as a solvent, a preservative, a means of lowering the freezing point of any drug. Another equally well-known representative of this class is methyl alcohol (also called wood alcohol or methanol). In contrast to ethanol methanol is deadly even in small doses! First, it causes blindness, then just "kills"!

Polyatomic alcohols

Polyatomic alcohols - alcohols that have multiple hydroxyl groups OH.
Diatomic alcohols are called alcoholscontaining two hydroxyl group (OH group); alcohols containing three hydroxyl groups - triatomic alcohols. In their molecules two or three hydroxyl groups never be attached to the same (one) carbon atom.
Dihydric alcohols also called glycol because they have a sweet taste, is characteristic of all polyatomic alcohols
Polyatomic alcohols with a small number of carbon atoms are a viscous liquids, high alcohols - solid substance. Polyatomic alcohols can be getting by the same synthetic methods as saturated polyatomic alcohols.

Getting the alcohol

1. Getting ethyl alcohol (wine alcohol) by fermentation of carbohydrates:
C2H12O6 => C2H5-OH + CO2

The essence of the fermentation is that one of the simplest sugars - glucose received in the technique from starch with the influence of the yeast breaks down into ethyl alcohol and carbon dioxide. It is established that the fermentation process are not themselves microorganisms, but substances secreted by them - simaz. To getting ethyl alcohol is usually used vegetable raw materials rich in starch: potatoes, wheat grain, rice, etc..

2. Hydration of ethylene with the presence of sulfuric or phosphoric acid
CH2=CH2 + KOH => C2H5-OH

3. The reaction of halogenoalkanes with alkali:
Alcohol reaction
4. The oxidation reaction of alkenes
Alcohol reaction

5. Hydrolysis of fats: in this reaction is got the well-known alcohol - glycerinAlcohol reaction
By the way, glycerin is found in many cosmetic products as a preservative and as a means of preventing the freezing and drying!

Properties of alcohols

1) Combustion: Like most organic substances alcohols burn to form carbon dioxide and water:
C2H5-OH + 3O2 -->2CO2 + 3H2O
During their combustion generates a lot of heat, which is often used in laboratories (laboratory burner). Lower alcohols burn almost colorless flame, and higher alcohols have yellowish color due to incomplete combustion of carbon.

2) Reaction with alkali metals
C2H5-OH + 2Na --> 2C2H5-ONa + H2
In this reaction formed hydrogen and alkoxid of sodium. Alkoxides similar to the salts of very weak acids, and they are easily hydrolyzed. The alkoxides are extremely unstable and in the water it's decomposed into alcohol and alkali. The conclusion is that the monatomic alcohols do not react with alkalis!

3) Reaction with the halogen-hydrogen
C2H5-OH + HBr --> CH3-CH2-Br + H2O
The reaction results is halogenoalkane (bromatan and water). This chemical reaction of alcohols is due not only to the hydrogen atom in the hydroxyl group, but due to hydroxyl group! But this reaction is reversible: for its occurrence need to separate the water, for example use sulfuric acid.

4) Intramolecular dehydration (with the presence of a catalyst H2SO4)
dehydration of alcohol
In this reaction with the action of concentrated sulfuric acid and the heat it is dehydration of alcohols. The reaction of the formed unsaturated hydrocarbon and water.
The cleavage of a hydrogen atom from alcohol can occur in the same molecule (i.e. redistribution of atoms in the molecule). This reaction is intermolecular dehydration reaction. For example, :
dehydration reaction
In the reaction process forms a simple ether and water.

5) Reaction with carboxylic acids:
Reaction with carboxylic acids
If you add to the alcohol carboxylic acid, for example, acetic, there will be the form the simple ether. But esters are less stable than simple ethers. If the reaction of formation simple ether almost irreversible, the esterification is a reversible process. Esters are readily hydrolyzed, breaking down into alcohol and carboxylic acid.

6)Oxidation of alcohols.
Еhe alcohols are not oxidized with oxygen in the air at ordinary temperature, but when heated and the presence of catalysts it oxidized. An example is copper oxide (CuO), potassium permanganate (KMnO4), chromium mixture. Different products got by the action of oxidants and depend on the structure of the original alcohol. Thus, primary alcohols are converted into aldehydes (reaction A), the secondary - to ketones (reaction B), and tertiary alcohols are resistant to oxidizing agents (C).
- A) for primary alcohols
окисление первичных спиртов
- B) for secondary alcohols
окисление вторичных спиртов
- C) tertiary alcohols by copper oxide is not oxidized!

As for polyatomic alcohols, they have a sweet taste, but some of them are poisonous. Properties of polyatomic alcohols similar to monoatomic alcohols, with the difference that the reaction is not one-to-hydroxyl group, but several at once.
One of the main distinctions - polyatomic alcohols easily react with copper hydroxide. This gives a transparent solution with bright blue-violet color. This reaction used to reveal the presence of a polyhydric alcohol in any solution.
Interact with nitric acid:
Alcohol reaction
To practical point the greatest interest is the reaction with nitric acid. The resulting nitroglycerin and dinitroEthylene glycol are used as explosives, and trinitroglycerin - and even in medicine as a vasodilator.

Ethylene glycol

Ethylene glycol - a typical representative of the polyatomic alcohols. Its chemical formula CH2OH - CH2OH. - dihydric alcohol. It is a sweet liquid that are able to dissolve in water in any proportions. In chemical reactions can be employed as a hydroxyl group (-OH), and two at the same time.
Ethylene glycol - its solutions are widely used as anti-icing agent (chemicals). Ethylene glycol freezes at a temperature of -340C and in the cold season can replace water, for example for cooling the cars.
With all the benefits of ethylene glycol you need to consider, it is a very strong poison!


We've all seen the glycerin. It is sold in pharmacies in the dark bubbles and is a viscous, colorless liquid, sweet taste. Glycerin is a trivalent alcohol. It is very well soluble in water, boils at a temperature 220 0C.
Chemical properties of glycerin are similar the properties of monoatomic alcohols, but glycerin can react with hydroxides of metals (with copper hydroxide Cu(OH)2), with the formation of glycerate metals are chemical compounds like a salts.
Reaction with copper hydroxide - the typical for glycerin. In the chemical reaction forms a bright blue solution of copper glycerate
copper glycerate


Emulsifiers is a higher alcohols, esters and other complex chemicals that, when mixed with other substances, such as fat, formed stable emulsions. By the way, all cosmetic products are also emulsions! As emulsifiers are often used substances, which are artificial wax (pental, sorbifolia), and triethanolamine, lecithin.


Solvents are substances used for the preparation of varnishes for hair and nails. They are presented in a narrow range, as most of these substances are can ignite and harmful to the human body. The most common representative of the solvent is acetone, and amyl acetate, butyl acetate, isobutyl.
There are also substances called diluents. They are usually used together with solvents for the preparation of various varnishes.
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Bases. Properties of bases. Alkali

Organic acids. Properties of carboxylic acids

Acetic acid. Formic acid

Potassium permanganate. Peroxide

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