Name Each Of The Following Alkenes.
The Correct Answer and Explanation is :
- Propene (C₃H₆): This is a simple alkene with three carbon atoms and a double bond between two of the carbon atoms. The name “propene” is derived from “prop-” for three carbon atoms and “-ene” indicating the presence of a double bond.
- Pentene (C₅H₁₀): This refers to an alkene with five carbon atoms and a double bond. It can have different isomers depending on where the double bond is located. For example, 1-pentene would have the double bond between the first and second carbon atoms, while 2-pentene would have the double bond between the second and third carbon atoms.
- 2-Pentene (C₅H₁₀): This is an isomer of pentene, where the double bond is between the second and third carbon atoms. The number “2” indicates the position of the double bond.
- 4-Pentene (C₅H₁₀): This would be another isomer of pentene, where the double bond would be between the fourth and fifth carbon atoms.
- 3-Pentene (C₅H₁₀): This is also an isomer of pentene, where the double bond is between the third and fourth carbon atoms.
- Trans-2-butene (C₄H₈): The term “trans” indicates that the two substituents on either side of the double bond are opposite each other (in the case of 2-butene, the two methyl groups are on opposite sides).
- 1-Hexene (C₆H₁₂): This is an alkene with six carbon atoms and a double bond between the first and second carbon atoms. The “1” before “hexene” indicates the location of the double bond.
- Cis-2-butene (C₄H₈): The term “cis” indicates that the two substituents on either side of the double bond are on the same side. In cis-2-butene, the methyl groups are on the same side of the double bond.
- Butene (C₄H₈): Butene can exist in different forms, with the double bond between the first and second carbons (1-butene) or the second and third carbons (2-butene).
Understanding the rules for naming alkenes involves identifying the longest carbon chain with the double bond, numbering the carbons starting from the end nearest the double bond, and using prefixes like “cis” and “trans” for stereochemistry when necessary.