alkanes (paraffins, saturated hydrocarbons) - biosoedineniya consisting only of C and H atoms in which all the atoms are connected by simple sigma bonds.The simplest of saturated hydrocarbons is methane.Each subsequent hydrocarbon of this series is different from the previous one by a group CH2.In this series of compounds neighboring members differ from each other by the difference in homology (CH2) similar homologous series are called.For such series are characterized by similar chemical properties and naturally changing physical properties.
synthesis alaknov main source - oil.It should be noted that it depends on the biochemical composition of the deposit.Unsaturated hydrocarbons are a valuable source for formaldehyde, methanol, chloroform, plastics, synthetic resins, ethers, acetone, glycerol, propylene, polypropylene, synthetic rubber butandienovogo, acetate acid etc.In industry alkanes obtained from shale and brown coal.Under normal conditions, alkanes - a chemically inert substance.At room temperature, they do not interact with any concentrated acid sulfate or the alkali metal or the caustic alkali.Paraffins readily undergo substitution reactions that proceed by a radical mechanism.The thermal conditions they can oxidize and undergo decomposition.
heptane isomers may be prepared as conventional methods of synthesis of alkanes, as well as through the provision of synthetic gasoline or oil.n-Heptane - colorless liquid with a faint characteristic odor, it is well soluble in organic solvents (ethanol, chloroform, diethyl ether).Heptane isomers, in particular triptane (2,2,3-trimethylbutane - CH3-C (CH3) 2-CH (CH3) -CH3) have practical use.This compound is used as additive to motor fuel.Isomers of heptane contained in the gasoline fractions of oil and gas condensate.n-heptane - primary standard in determining the properties of the detonation of the carburettor fuel.During the reforming of n-hexane was converted into isomers of heptane, then aromatic compound in degidrotsikliziruetsya - toluene.
in organic chemistry widespread phenomenon of isomerism.There are two basic types of isomerism - structural and stereoisomers.Each type can be divided into types: isomerism hydrocarbon chain placement of double bonds and functional groups to the carboxylic radical metamerism isomer benzelnom arrangement of substituents in the nucleus.A special place among stereoisomerism takes optical isomers.This type is associated with the ability of certain groups of organic compounds in the solutions exhibit optical activity.Substances which are capable of exhibiting optical activity of optically active compounds are called.Isomerism of organic compounds is determined using a special device - a polarimeter.The device is equipped with two Nicols, analyzer, polarimetric tube.
Optically active compounds usually exist as two optical isomers.They are called optical antipodes or enantiomers.A mixture composed of equimolar amounts of enantiomers, optically inactive, called a racemate or racemic compound.Racemates designated sign ±.The simplest optically active substance is lactate acid molecule in which there is one asymmetric carbon atom the valency of which are connected to four different substituents of - hydrogen, hydroxyl, methyl, and carboxyl groups.
each organic compound having in its molecule has an asymmetric carbon atom exists in the form of spatial shapes (patterns) with the same amount of the same atoms and groups arranged around the asymmetric carbon, so that when combining them (shapes, patterns) inSpace is impossible to achieve a match.These models are similar as the right and left hand of the person or an object and its mirror image.Therefore, they are called chiral isomers, isomer - optical or mirror.
