Headings Hydrocarbons Search Questions 
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Alkanes and Alkenes - Uses.
Alkanes are unreactive and are mainly used as fuels.
Alkenes are much more reactive than
alkanes
because alkenes are unsaturated (they have a
reactive double bond).
Alkenes are the starting
material for many different
chemicals.
They are extremely useful to the
chemical industry.
Ethene and propene are the starting
materials for polymers,
giving poly(ethene) and poly(propene) - see
polymers.
An alkene may be distinguished from an alkane
by shaking the hydrocarbon with
bromine water.
Bromine water is brown, and
will lose its colour with an alkene
but not with an alkane.
Bromine adds across
the double bond of an alkene
to form a colourless dibromo
alkane.
This is an example of an addition
reaction.
An addition reaction occurs when two or more reactants
join together to form a single
product.
Other examples of addition
reactions are the hydrogenation of
vegetable oils,
addition
polymerisation and the hydration of
ethene.
Headings Hydrocarbons Search Questions
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