Ethene

Definition

Ethene, also known as ethylene, is a colorless gas with the chemical formula C₂H₄. It is the simplest alkene and is characterized by its carbon-carbon double bond, which plays a crucial role in the molecule's reactivity and bonding properties. Understanding ethene involves looking at its hybridization and bonding, as the structure directly influences its behavior in chemical reactions and its use in various applications such as plastics and agriculture.

5 Must Know Facts For Your Next Test

1. Ethene has a trigonal planar geometry around the carbon atoms due to sp² hybridization, leading to bond angles of approximately 120 degrees.
2. The double bond in ethene consists of one sigma (σ) bond and one pi (π) bond, which influences its reactivity compared to alkanes.
3. Ethene can undergo various reactions such as polymerization, where it can be converted into polyethylene, a widely used plastic.
4. Due to its role as a plant hormone, ethene is important in regulating processes like fruit ripening and leaf abscission.
5. Ethene's boiling point is -104 °C, which makes it a gas at room temperature; this physical property affects its handling and storage.

Review Questions

• How does the hybridization of carbon atoms in ethene contribute to its molecular structure and bonding?
  • In ethene, each carbon atom undergoes sp² hybridization, forming three sp² hybrid orbitals that are oriented in a trigonal planar arrangement. This allows for the formation of one sigma bond with another carbon atom and two sigma bonds with hydrogen atoms. The remaining unhybridized p orbital on each carbon overlaps to form a pi bond, creating the characteristic double bond that defines ethene’s structure and influences its reactivity.
• Discuss the implications of cis-trans isomerism in ethene and how it affects the properties of compounds derived from it.
  • Cis-trans isomerism occurs in alkenes like ethene due to the restricted rotation around the carbon-carbon double bond. In compounds derived from ethene, this leads to different spatial arrangements of substituents around the double bond, significantly affecting their physical properties such as boiling points and solubility. For example, cis isomers may have higher boiling points than their trans counterparts due to increased polarity, influencing their behavior in reactions and applications.
• Evaluate the role of ethene in both industrial applications and biological processes, highlighting its significance.
  • Ethene plays a dual role in industrial applications and biological processes. Industrially, it serves as a key feedstock for producing polyethylene through polymerization, contributing to the vast plastics industry. Biologically, ethene acts as a plant hormone that regulates vital processes such as fruit ripening and leaf drop, showcasing its importance in agriculture. Understanding these roles illustrates how ethene is not just a simple hydrocarbon but also an essential compound influencing both technology and nature.

Related terms

Alkene: A class of hydrocarbons that contain at least one carbon-carbon double bond, characterized by their unsaturation.

Hybridization:

The concept of mixing atomic orbitals to form new hybrid orbitals, which explain the bonding geometry and properties of molecules.

Cis-Trans Isomerism: A type of stereoisomerism that occurs in alkenes due to the restricted rotation around the carbon-carbon double bond, leading to distinct geometrical arrangements.