-en-

Definition

The suffix '-en' is used in organic chemistry to indicate the presence of a carbon-carbon double bond, known as an alkene or olefin, within a molecule. This term is particularly relevant in the context of 9.1 Naming Alkynes, as it helps distinguish the structural features and naming conventions for this class of unsaturated hydrocarbons.

5 Must Know Facts For Your Next Test

1. The '-en' suffix is used to indicate the presence of a carbon-carbon double bond in the parent chain of an alkane.
2. The location of the double bond is specified by a number that indicates the position of the first carbon involved in the double bond, counted from the end of the parent chain.
3. Alkynes, which contain a carbon-carbon triple bond, are named using the '-yne' suffix instead of '-en'.
4. The presence of a double bond affects the physical and chemical properties of the molecule, such as boiling point, reactivity, and stability.
5. Alkenes are more reactive than alkanes due to the presence of the carbon-carbon double bond, which can undergo various addition reactions.

Review Questions

• Explain the purpose of the '-en' suffix in the context of naming alkynes.
  • The '-en' suffix is used in organic chemistry to indicate the presence of a carbon-carbon double bond within a molecule. In the context of naming alkynes, the '-en' suffix is used to distinguish the structural features of these unsaturated hydrocarbons from those containing a carbon-carbon triple bond, which are named using the '-yne' suffix. The location of the double bond is specified by a number that indicates the position of the first carbon involved in the double bond, counted from the end of the parent chain.
• Describe how the presence of a carbon-carbon double bond affects the physical and chemical properties of an alkene.
  • The presence of a carbon-carbon double bond in an alkene molecule affects its physical and chemical properties. Compared to alkanes, alkenes generally have lower boiling points due to weaker intermolecular forces. Additionally, the double bond makes alkenes more reactive, as they can undergo various addition reactions, such as hydrogenation, halogenation, and hydration. The reactivity of alkenes is due to the presence of the pi bond, which is less stable than the sigma bonds found in alkanes and can be more easily broken to form new bonds with other atoms or molecules.
• Analyze the relationship between the '-en' suffix and the '-yne' suffix in the context of naming unsaturated hydrocarbons.
  • The '-en' and '-yne' suffixes are both used in organic chemistry to name unsaturated hydrocarbons, but they indicate different types of carbon-carbon bonds. The '-en' suffix is used to denote the presence of a carbon-carbon double bond, while the '-yne' suffix is used to indicate a carbon-carbon triple bond. This distinction is crucial in the context of naming alkynes, as it allows for the clear identification of the structural features of the molecule and the reactivity associated with the type of unsaturated bond present. Understanding the relationship between these two suffixes is essential for accurately naming and differentiating between various classes of unsaturated hydrocarbons.

Related terms

Alkene: An unsaturated hydrocarbon containing at least one carbon-carbon double bond.

Olefin: Another term used to describe an alkene, derived from the Greek word 'olefiant' meaning 'oil-forming'.

Unsaturated Hydrocarbon: A hydrocarbon that contains at least one carbon-carbon double or triple bond, resulting in fewer hydrogen atoms than the corresponding saturated hydrocarbon.