The vital force theory received a severe blow when wohler prepared urea in the laboratory from inorganic compound ammonium cyanate in the laboratory. The unique properties of carbon such as tetravalency, catenation and formation of multiple bonds are responsible for it to form millions of compounds.
Carbon shares four electrons with other atoms and forms four single covalent bonds and it is known as tetravalency. The property of self linkage among identical atoms to form long chain compounds is known as catenation. , n-butane is a straight chain compound, 2-methyl butane is a branched chain compound, and cyclobutane is a cyclic compound.
Compounds of carbon linked by single bonds are known as saturated compounds. Example methane, ethane. The compounds of carbon linked by double and triple bonds are called unsaturated compounds. Example – ethene and ethyne.
The compounds of carbon which contain a closed ring of carbon atoms are regarded as cyclic hydrocarbons. They are of two types.
Cyclo propane and cyclo butane are alicyclic compounds and benzene is an aromatic compound.
The carbon atom together with hetero atoms is known as functional group. When carbon compounds with same functional group are arranged in ascending order of their molecular weights, the difference between the two consecutive members of the series is –CH2 and such a series is called homologous series.