Diamond a different story

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					Carbon has different allotropes. One of the allotropes is diamond, which is hard and
clear. The other allotropes graphite and charcoal are soft black. The differences between
these allotropes are very great. Diamonds are used to cut and engrave glass, but graphite
and charcoal are used by artists to get soft, shaded effect. Diamond, graphite and charcoal
are all pure carbon. When they burn in excess oxygen, the only product is carbon dioxide.
But these allotropes have different densities. This means that their atoms are not packed
in same way. The arrangement of carbon atoms in diamond, graphite and charcoal has
been studied by X-ray analysis.

                  Diamonds are very hard. Carbon atoms in diamond are linked by very
strong covalent bonds. This makes diamond hard. Another reason for hardness is that the
atoms are not arranged in layers so they can not slide over one another like atoms of
metals. Diamond is one of the hardest known substances. Diamonds which are not good
enough for gems are used in glass cutters and diamond studded saws.

                     Diamonds has very high melting point. Carbon atoms in diamond are
held in the crystal structure by very strong covalent bonds. This means that the atoms can
not vibrate fast enough to break away from their neighbours until very high temperatures
are reached. Diamond does not conduct electricity. In diamond outer electrons of each
carbon atom are held firmly in covalent bonds. So, diamond does not conduct electricity

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Description: This document tells about different forms of carbon and their behaviour. It also explains properties and uses of diamond.