Fri November 18, 2011 By: Gautam Udayabhanu

Please explain easy techniques to draw the structural formula of Alkanes Alkenes Alkynes etc....and the techinique to write their condensed formula?

Expert Reply
Mon November 21, 2011

Hydrocarbons that don't contain benzene-like rings, in contrast to aromatic hydrocarbons.
Alkane  -  Aliphatic hydrocarbon that consists of all single bonds.
Alkene  -  Aliphatic hydrocarbon that contains C=C double bonds.
Alkyne  -  Aliphatic hydrocarbon that contains C-C triple bonds.
Condensed formula is a way to draw structures in an abbreviated way of writing organic molecules in which C-H bonds are omitted. C-C bonds can also be omitted sometimes.
Lets understand this using examples.

Pentane (C5H12) can exhibit the following three structures.

A condensed structural formula omits the single bonds to hydrogens. Sometimes even the carbon-carbon bonds are omitted. For example, hexane can be drawn using the following condensed structures.

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