7.2.1

Structure of Alkenes

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Alkenes

Alkenes are hydrocarbons with the functional group C=C. This means that alkenes have a carbon-carbon double bond. Alkenes have the following features:

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Unsaturated

  • Alkenes are unsaturated hydrocarbons because they contain a double bond between two of their carbon atoms (C=C).
  • This means that an alkane and alkene with the same length of carbon chain will have different numbers of hydrogen atoms - the alkane will have two more hydrogen atoms.
Illustrative background for What is the general formula of alkenes?Illustrative background for What is the general formula of alkenes? ?? "content

What is the general formula of alkenes?

  • A homologous series is a series of compounds with the same general formula.
  • Alkenes are a homologous series with the general formula CnH2n.
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How reactive are alkenes?

  • The presence of the C=C functional group means that alkenes have greater reactivity than alkanes.

The 4 Shortest Alkenes

The four shortest alkenes, in ascending (increasing) size order, are:

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Ethene

  • Ethene has the formula C2H4
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Propene

  • Propene has the formula C3H6
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Butene

  • Butene has the formula C4H8
Illustrative background for PenteneIllustrative background for Pentene ?? "content

Pentene

  • Pentene has the formula C5H10

Jump to other topics

1Atomic Structure

2Chemical Bonding

3Quantitative Chemistry

4Chemical Changes

5Energy Changes

6The Rate & Extent of Chemical Change

7Organic Chemistry

8Chemical Analysis

9Chemistry of the Atmosphere

10Using Resources

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