Difference Between Ethane and Ethene

Main Difference – Ethane vs Ethene

Hydrocarbons are molecules composed of carbon (C) and hydrogen (H) atoms. The majority of hydrocarbons are found in crude oil. Ethane and Ethene are such hydrocarbons that have simple molecular structures but are very useful in many industries. Ethane is a saturated hydrocarbon. It has no double bonds. Ethene is an unsaturated hydrocarbon. It has a double bond. However, both are aliphatic hydrocarbons since they are not cyclic structures. The main difference between ethane and ethene is that the carbon atoms of ethane are sp³ hybridized whereas the carbon atoms in ethene are sp² hybridized.

Key Areas Covered

1. What is Ethane
      – Definition, Properties, Applications
2. What is Ethene
      – Definition, Properties, Applications
3. What are the Similarities Between Ethane and Ethene
      – Outline of Common Features
4. What are the Difference Between Ethane and Ethene
      – Comparison of Key Differences

Key Terms: Aliphatic, Ethane, Ethene, Ethylene, Hybridization, Hydrocarbons, Pi Bond, Sigma Bond

What is Ethane

Ethane is a hydrocarbon composed of two carbon atoms and six hydrogen atoms. It is a saturated hydrocarbon that has no double bonds in its structure. The two carbon atoms are bonded to each other through a covalent bond. Hydrogen atoms are bonded to the carbon atoms through single bonds. Three hydrogen atoms are attached to each carbon. The carbon atoms of ethane are sp³ hybridized. Therefore, there are no un-hybridized p orbitals to form pi bonds. Therefore, there are only sigma bonds present in ethane.

Figure 1: Molecular Structure of Ethane

The molar mass of ethane is about 30.07 g/mol. It is a colorless and odorless gas at room temperature and atmospheric pressure. The melting point of ethane is about -182.8^oC. The chemical formula of ethane is given as C₂H₆. Since there are no double bonds, ethane can be categorized as an alkane. Ethane is the second most important constituent in natural gas.

Ethane is flammable; therefore, it is combustible. It is a component in natural gas. Ethane is also used as a reactant for the production of ethylene. Since ethylene is an essential component in a number of industries, it is very important as a reactant. Moreover, ethane is a refrigerant used that is used in refrigeration systems that cause cooling.

What is Ethene

Ethene is a hydrocarbon that is composed of two carbon atoms and four hydrogen atoms. The chemical formula of ethene is C₂H₄. The two carbon atoms are bonded to each other through a double bond. Therefore, ethene is an unsaturated hydrocarbon. The two carbon atoms are sp² hybridized. The molecular geometry of ethene is planar.

Figure 2: Molecular Structure of Ethene

The molar mass of ethene is about 28.05 g/mol. The melting point of ethene is -169.2^oC. In room temperature and atmospheric pressure, ethene is a colorless gas with a characteristic odor. The bond angle between bonds of ethene is about 121.3^o. Since the carbon atoms are composed of un-hybridized p orbitals, these orbitals can form a pi bond between the two carbon atoms. This double bond causes the reactivity of ethene.

The common name for ethene is ethylene. It is used in the production of polymer materials like polyethylene through the polymerization of ethene monomer. Ethylene also acts a major role in plants as a hormone that regulates the ripening of fruits.

Similarities Between Ethane and Ethene

Ethane and Ethene molecules are composed of carbon and hydrogen atoms.
Both are composed of two carbon atoms.
Both are hydrocarbons.
Both are aliphatic organic molecules.

Definition

Ethane: Ethane is a hydrocarbon composed of two carbon atoms and six hydrogen atoms.

Ethene: Ethene is a hydrocarbon composed of two carbon atoms and four hydrogen atoms.

Chemical Formula

Ethane: The chemical formula of ethane is C₂H₆.

Ethene: The chemical formula of ethene is C₂H₄.

Hybridization of Carbon

Ethane: The carbon atoms of ethane are sp³ hybridized.

Ethene: The carbon atoms of ethene are sp² hybridized.

Molar Mass

Ethane: The molar mass of ethane is about 30.07 g/mol.

Ethene: The molar mass of ethene is about 28.05 g/mol.

Melting Point

Ethane: The melting point of ethane is about -182.8^oC.

Ethene: The melting point of ethene is about -169.2^oC.

Bond Angle

Ethane: The bond angle of H-C-C bond in ethane is about 109.6^o.

Ethene: The bond angle of H-C-C bond in ethene is about 121.7^o.

C-C Bond Length

Ethane: The C-C bond length in ethane is about 154 pm.

Ethene: The C-C bond length in ethene is about 133 pm.

C-H Bond Length

Ethane: The C-H bond length in ethane is about 110 pm.

Ethene: The C-H bond length in ethene is about 108 pm.

Conclusion

Both ethane and ethene can be found as major components in natural gas. Those are highly flammable and combustible. Although ethene can be used as a monomer for the production of polymers, ethane cannot be used for this purpose. This is because ethane does not have either a double bond or a functional group. This is the main difference between ethane and ethane.

References:

1. “Ethane: Structure, Uses & Formula.” Study.com. Study.com, n.d. Web.Available here. 03 Aug. 2017.
2. “Ethylene.” Wikipedia. Wikimedia Foundation, 30 July 2017. Web. Available here. 03 Aug. 2017.
3. “Ethane.” Encyclopædia Britannica. Encyclopædia Britannica, inc., n.d. Web. Available here. 03 Aug. 2017.

Image Courtesy:

1. “Ethane-2D-flat” (Public Domain) via Commons Wikimedia
2. “Ethene structural” By McMonster – Own work (Public Domain) via Commons Wikimedia