Lecture Notes: Hydrocarbons and Types of Carbons

Introduction to Hydrocarbons

• Definition: Organic compounds composed primarily of carbon and hydrogen.
• Types of Hydrocarbons:
  • Aliphatic Hydrocarbons: Can be saturated or unsaturated.
  • Aromatic Hydrocarbons: Contain aromatic rings.

Properties of Hydrocarbons

• Insolubility in Water: Due to non-polarity of carbon-carbon and carbon-hydrogen bonds.
• Polarity: Hydrocarbons are typically non-polar, thus not soluble in polar solvents like water.

Categories of Aliphatic Hydrocarbons

• Saturated Hydrocarbons (Alkanes):

  • Contain only carbon-carbon single bonds.
  • Cannot add more hydrogen; fully saturated.
  • General Formula for Chains: ( C_nH_{2n+2} )
  • General Formula for Rings: ( C_nH_{2n} )

• Unsaturated Hydrocarbons:

  • Alkenes:
    • Contain carbon-carbon double bonds.
    • General Formula: ( C_nH_{2n} )
  • Alkynes:
    • Contain carbon-carbon triple bonds.
    • General Formula: ( C_nH_{2n-2} )

Aromatic Hydrocarbons

• Structure: Characterized by aromatic rings with alternating double and single bonds.
• Benzene: A primary example of aromatic hydrocarbons.

Identifying Hydrocarbons

• Use molecular formulas to determine if a compound is an alkane, alkene, or alkyne using respective general formulas.

Types of Carbons in Organic Chemistry

• Primary Carbon: Connected to one other carbon atom.
• Secondary Carbon: Connected to two carbon atoms.
• Tertiary Carbon: Connected to three carbon atoms.

Example Problems

• Identifying types of carbons and hydrogens in given structures such as butane and isobutane.
  • Butane: Contains primary and secondary carbons, with respective primary and secondary hydrogens.
  • Isobutane: Contains primary, secondary, and possibly tertiary carbons and hydrogens based on structure.

Summary

• Memorize general formulas for different types of hydrocarbons to identify their saturation status and type.
• Recognize the differences between aliphatic and aromatic hydrocarbons based on their structure and bonding.