Chemistry Homologous Series

Homologous Series:

A homologous series is a family of hydrocarbons with similar chemical properties who share the same general formula.

An example of a homologous series would be the Alkanes:

Alkanes consist of ONLY hydrogen and carbon. There will always be a chain of carbon in the midle, with the hydrogens forming around it.

Alkanes have a general formula of CnH2n+2.

We only need to know up to octane for National 5. So, Methane, Ethane, Propane, Butane, Pentane, Hexane, Heptane and Octane.

Naming Branches Chain Alkanes:

There are some general rules which you should remember when naming organic compounds:

The longest unbranched chain containing the functional group is the main molecule or simply the longest unbranched chain for alkanes. Remember that the longest chain can go round a bend.

Indicate the position of the functional group with a number, numbering from the end nearest the functional group.

Name the branches, and indicate the number of branches.

Alterations:

Methyl indicates there is one carbon atom in the branch.

Ethyl indicates there are two carbon atoms in…