The use of alkanes is quite diverse - they are used as fuel, as well as in mechanics, medicine, etc. The role of these chemical compounds in the life of modern man is difficult to overestimate.
Alkanes: properties and a brief description
Alkanes are non-cyclic carbon compounds in which carbon atoms are linked by simple saturated bonds. These substances represent a whole series with certain properties and characteristics. The general formula of alkanes is as follows:
Cnh2n + 2
N here represents the number of carbon atoms. For example, CH3, C2H6.
The first four representatives of a number of alkanes - gaseous substances - are methane, ethane, propane and butane. The following compounds (C5 to C17) are liquids. The series continues with compounds which, under normal conditions, are solids.
As for the chemical properties, alkanes are inactive - they practically do not interact with alkalis and acids. By the way, it is the chemical properties that determine the use of alkanes.
Nevertheless, some reactions are characteristic of these compounds, including the substitution of hydrogen atoms, as well as the processes of molecular cleavage.
- The most characteristic reaction is halogenation, in which hydrogen atoms are replaced by halogens. Of great importance are the reactions of chlorination and bromination of these compounds.
- Nitration - the substitution of a hydrogen atom by a nitro group during a reaction with dilute (concentration 10%) nitric acid. Under normal conditions, alkanes do not interact with acids. In order to carry out a similar reaction, a temperature of 140 ° C is needed.
- Oxidation - Under normal conditions, alkanes are not susceptible to oxygen. However, after ignition in air, these substances enter into a combustion reaction, the final products of which are water and carbon dioxide.
- Cracking - this reaction takes place only with the necessary catalysts. In the process, the splitting of persistent homological bonds between carbon atoms occurs. For example, by cracking butane, ethane and ethylene can be obtained from the reaction.
- Isomerization - as a result of exposure to some catalysts, some rearrangement of the carbon skeleton of the alkane is possible.
The use of alkanes
The main natural source of these substances are such valuable products as natural gas and oil. Scopes of alkanes today are very wide and varied.
For example, gaseous substances are used as a valuable source of fuel. An example is methane, of which natural gas is composed, as well as a propane-butane mixture.
Another source of alkanes is oil , the importance of which for modern mankind is difficult to overestimate. Petroleum products include:
- gasolines - are used as fuel;
- kerosene;
- diesel fuel, or light gas oil;
- heavy gas oil, which is used as a lubricating oil;
- residues of oil distillation are used for the manufacture of asphalt.
Petroleum products are also used to make plastics, synthetic fibers, rubbers and some detergents.
But the use of alkanes is much wider. Some liquid forms of these substances are used as solvents, as well as rocket fuel.
Vaseline and liquid paraffin are products that consist of a mixture of alkanes. They are used in medicine and cosmetology (mainly for the preparation of ointments and creams), as well as in perfumes.
Paraffin is another well-known product that is a mixture of solid alkanes. This is a solid white mass, the heating temperature of which is 50 - 70 degrees. In modern production, paraffin is used to make candles. Matches are impregnated with the same substance. In medicine, various types of thermal procedures are carried out using paraffin.