Isomers of heptane: a general characteristic and application
Isomers of heptane: a general characteristic and application
Heptane is an organic substance with the formula C7H16. It is a liquid with a density of about 0.7 g / cm3. Due to the fact that in its molecule there are no double or triple bonds, and the polarization of the bond between the carbon and hydrogen atoms is rather weak, the heptane is fairly stable from the chemical point of view.
General Characteristics of Heptane Isomers
Heptane with difficulty enters into any reaction. There are nine isomers of this organic substance (and if we also assume optical isomers, we can isolate 11 isomers). All of them have the same empirical formula C7H16, but differ in structure and, accordingly, in physical properties. All isomers of heptane are colorless transparent flammable liquids with a sharp odor. Their boiling point ranges from 79.20 ° C (2.2-dimethylpentane) to 98.43 ° C (n-heptane). A density lies in the range from 0.6727 grams / cm3 (2,4-dimethylpentane) to 0.6982 grams / cm3 (3-ethylpentane). The heptane isomers are practically insoluble in water, but are readily soluble in many organic liquids. They are inactive, but can participate in reactions that occur with the formation of free radicals. For example, in halogenation reactions, at elevated temperature or UV irradiation. However, fluorination, chlorination or bromination of heptane isomers can be carried out in this way, and iodine does not react with these substances. It is known that isomers of heptane can also participate in the reactions of sulfochlorination, catalytic oxidation. They are able to decompose (this requires either a very high temperature, over 1000 ° C, or the presence of a special catalyst, which makes it possible to carry out the reaction at lower temperatures, of the order of 400-500 ° C), and also burn in an oxygen atmosphere to form water and carbon dioxide. This reaction proceeds according to the following formula: 2 C7H14 + 21O2 = 14CO2 + 14H2O For a lack of oxygen, the reaction can lead to either the formation of carbon monoxide, the formula looks like this: C7H14 + 7O2 = 7CO + 7H2O. Or to the formation of carbon. In this case, it can be recorded as a reaction: 2C7H14 + 7O2 = 14C + 14H2O How heptane isomers are used
N-Heptane serves as raw material for the production of certaintypes of organic compounds. In addition, it is used as a primary standard in determining the detonation properties of fuel, since its octane number (an indicator characterizing the ability of a fuel to resist self-ignition upon compression) is 0. And one of the isomers of this organic substance, 2,2,3-Trimethylbutane, increases the octane number of fuel, and is therefore widely used as an additive to it.
