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What is an Alkane?

Alkanes are organic molecules that form an homologous
series
with the general formula CnH2n+2. Homologous series
means that the series has the same general formula and
the
compounds have similar properties and structure, differing
only in the number of CH2 units in the chain. The "chain"
is the line of carbon atoms joined together. Members
of
the
same series show a gradual change in physical
properties
for example the boiling point increases as the chain gets longer.

Methane, CH4, has n=1. Pentane, C5H12, has n=5.
Ethane, C2H6, has n=2. Hexane, C6H14, has n=6.
Propane, C3H8, has n=3. Heptane, C7H16, has n=7.
Butane, C4H10, has n=4. Octane, C8H18, has n=8.

Below are links to the structure of some alkanes.
Some of these molecules exist as isomers. The
structural formula is sometimes called the displayed formula.

Methane      Ethane      Propane      Butane

Pentane      Hexane      Heptane      Octane

Alkanes are hydrocarbons that have single bonds between
all of the atoms. They have the maximum number of
hydrogen atoms for the number of carbon atoms present,
and so alkanes are called saturated hydrocarbons.

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