ACKNOWLEDGEMENT:
Figure
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Source of Figure
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Figure 18a
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www.medcoat.us
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Figure 18b
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www.medcoat.us
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Carbon & its
Allotropes:
Allotropes: Allotropes are different physical forms of the same
element. For example, Carbon exists in 2 allotropes of Graphite and Diamond.
Graphite is black and greasy, while diamond is the hardest material known to
mankind.
Graphite:
Carbon is graphite forms a hexagonal layered structure by
sharing 3 of its 4 electrons.
Figure 18a:
These layer give the graphite its application as a lubricant. 1
out of its 4 electron per carbon atom remains a free electron in the structure
and this free electron enables graphite to conduct electricity when a potential
difference is applied perpendicular to the hexagonal planes. Free electrons
flow parallel to the planes to conduct electricity.
Figure 18b:
The covalent bonds are strong and rigid and gives graphite its
high melting and boiling point.
Table 9: Properties of Graphite
