Introduction to Organic Chemistry

The following topics are covered in this Section:

• Basic concepts
• Alkenes
• Hydrocarbons from oil
• Alcohols
• Alkane
• Halogenoalkanes

 Basic concepts

• After studying this section you should be able to:
• understand the different types of formula used for organic compound
• understand the terms saturated and unsaturated hydrocarbon
• understand what is meant by structural isomerism
• recognise the alkanes and alkyl groups
• understand what is meant by a homologous series
• recognise common functional groups
• apply rules for naming simple organic compounds
• understand the difference between homolytic and heterolytic fission
• calculate percentage yields

Types of formula

In organic chemistry, there are many ways of representing a formula. 

For the compound butane, with 4 carbon atoms and 10 hydrogen atoms:

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Carbon chains

Hydrocarbons

Hydrocarbons are compounds of carbon and hydrogen only.

• A saturated hydrocarbon has single bonds only.

• An unsaturated hydrocarbon contains a multiple carbon carbon bond.

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Alkanes

Carbon atoms can bond with other carbon atoms to form an enormous range of compounds with different carbon-chain lengths. The simplest organic compounds are a family of saturated hydrocarbons called the alkanes, shown below.

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Note the following points.

• The name of the alkane ends with –ane.
• The prefixes (meth-, eth-, …) are used to represent the number of carbon atoms. You will need to use these many times in organic chemistry and they must be learnt.

General formula

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Homologous series

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Note that physical properties, such as boiling point and density, do gradually change as the length of the carbon chain increases.