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Isomers of Alkenes.
Changing the position
of the double
bond in an alkene
makes a
different isomer.
Butene and pentene exist as
different isomers.
Compare these with the isomers of
butane and pentane on the previous
pages.
Butene
(C4H8) is commonly represented by
the molecule but-1-ene
which has
the structural formula
Other isomers of butene
can be drawn by changing the place of
the double bond
or by changing the way that the
carbon atoms are joined to each other.
The other isomers of butene are
but-2-ene
represented by the structural formula
and 2-methylpropene, represented by the structural formula
where the double lines between
the carbon atoms
represent a double
covalent bond.
The single lines represent single covalent
bonds.
Note that each carbon atom has
four bonds
(valency 4),
and each hydrogen atom has one bond
(valency 1).
Valency is the combining power of an atom.
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Copyright © 2008 Dr. Colin France. All Rights Reserved.