The simplest organic compounds are hydrocarbons. All organic compounds can be derived from hydrocarbons by substituting a hydrogen atom with a suitable functional group. Replacing a hydrogen atom by a OH group in a hydrocarbon, gives an alcohol: replacement of H atom in a hydrocarbon by COOH group gives in a hydrocarbon carboxylic acid, and so on.
Lower alkenes are used as fuel and illuminant. These may be obtained by the cracking of kerosene or petrol.
Alkynes are generally used as the starting materials for the manufacture of a large number of organic compounds of industrial importance such as, chloroprene, vinyl chloride etc.
Benzene is used as a starting material for dyes, drugs, perfumes and explosives and polymers
Until the early years of the nineteenth century, only the plants and animals were the known sources of organic compounds. With the advent of the Industrial Revolution in Europe, fossil fuels like coal and petroleum gained prominence as the sources of organic compounds, particularly hydrocarbons. Today, hydrocarbons are mostly obtained from petroleum. In recent years coal has started gaining prominence, probably due to the uncertain conditions in the world oil market.
Synehtetic Petrol :The petrol obtained artificially from coal as a mixture of alkanes resembling petroleum like aliphatic hydrocarbon fuels is called synthetic petrol. Two important methods for producing synthetic petrol are the Fischer-Tropsch process and the Bergius process. These processes were developed in Germany during World War II, when its petroleum supplies were cut off. Germany produced considerable amounts of fuel from coal by the above processes during that period.