Carbon Compounds
Carbon is very special because it can form so many compounds.
The explanation lies deep inside the atom. Carbon atoms can form strong links with four other atoms. This dramatically increases the
number of patterns that carbon atoms can make.
Carbon can also link together in long chains or rings, carbon to
carbon to carbon to carbon and so on. Chemists call these links chemical bonds; very long chains, made by joining short ones, are
called polymers. And, quite unusually, these long chains cannot be destroyed by water or air or be attacked by bacteria. This explains
why so many plastics do not disintegrate in the environment in the way that other materials do. Only sunlight can destroy some
polymers, causing the chains to break, and the material to become brittle.
Carbon is part of many compounds, all of which have certain
common properties. For example:
1 Few carbon based-compounds change quickly at ordinary temperatures, but they begin to react fiercely at high temperatures
(as in burning).
2 All carbon compounds that form tissues plants, tar, oil, natural
gas, etc. will burn (they are combustible) and can be used as a fuel. When they burn, the compound is oxidised and carbon
dioxide is produced. The remaining material is nearly pure carbon (which can be seen in the charred nature of burnt wood, for
example).
3 Many carbon-based compounds are not attracted to water and
so in general do not dissolve in water. As a result, water alone cannot be used to remove grease or oil from a surface, nor will
water dissolve our skin, because all of these things are carbon compounds.
4 Groups that contain carbon and nitrogen often have an unpleasant smell in liquid form. Some people compare it to rotting
fish. Such smells are mainly confined to the factories where the materials are made. The common fabric material nylon, for
example, which is a plastic that contains nitrogen, has no smell once it is made into a yarn.
5 Some compounds of carbon and nitrogen are very unstable and
can be made into explosives. Two of the more common explosives are TNT (trinitrotoluene) and nitroglycerine (glycerol trinitrate).