chapter 4 carbon and its compound dec 2015 | Page 2

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It is evident that the number of shared pair of electrons can be one, two or
three. Try making the structures of H2O and CH4.

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Bond formed by the sharing of an electron pair between two atoms is called
covalent bond.

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Covalently bonded molecules have low melting and boiling points because of
comparatively weaker intermolecular forces, unlike ionic compounds.

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These molecules are generally poor conductor of electricity since no charged
particles are formed.

Versatile Nature of Carbon Atoms:
Two important properties of carbon atom enable carbon to form enormously large
number of compounds.

CATENATION : property of carbon atom to form bond with other atoms of
carbon is called catenation. Like carbon, silicon forms compounds with hydrogen
upto seven or eight atoms of silicon.
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