Hydrocarbon Derivatives and Functional Groups (Lesson 5)

• Functional groups


  Groups of atoms contained within a larger molecule that have characteristic chemical properties
• Functional groups introduced


  • Alkene
  • Alkyne
  • Hydroxyl group
  • Alkoxy group
  • Amino group
  • Halide group
  • Formyl group
  • Carbonyl group
  • Carboxyl group
  • Ester group
  • Amide group
• Hydrocarbons with functional groups


  • Part of the aliphatics group
  • Hydrocarbon derivatives are formed
• Hydroxyl group


  Oxygen single bonded to a hydrogen
• Types of alcohols

  • Primary (1°) alcohol
  • Secondary (2°) alcohol
  • Tertiary (3°) alcohol
• Properties of alcohols


  • Presence of polar O-H bond
  • Higher boiling point than parent alkane
  • Soluble in water
  • Long chain alcohols soluble in nonpolar solvents
• Alkoxy group


  Oxygen single bonded to carbon on both sides
• Properties of ethers


  • Cannot form hydrogen bonds
  • Contain polar C-O bonds
  • Boiling point lower than alcohol, higher than hydrocarbon
  • Good solvents for organic reactions
• Amino group

  Nitrogen single bonded to carbon, with hydrogens or carbons on other 2 sides
• Amines

  • Ammonia molecule with one or more hydrogen atoms replaced by alkyl groups
  • Subclassified by number of alkyl groups attached to nitrogen
• Properties of amines


  • N-H bonds in primary/secondary amines allow hydrogen bonding
  • Tertiary amines cannot form hydrogen bonds
  • Smaller amines very soluble in water
• Halide group

  Halogen single bonded to carbon
• Properties of haloalkanes


  • Smaller ones slightly soluble in water, larger ones insoluble
  • Higher melting/boiling points than alkanes due to increased London dispersion forces
• Formyl group

  Carbon double bonded to oxygen, with at least one hydrogen
• Properties of aldehydes


  • Contain polar C=O bonds
  • Boiling point lower than alcohol, higher than hydrocarbon
  • Small aldehydes soluble in water, larger ones less soluble
  • Good solvents for organic reactions
• Carbonyl group


  Carbon double bonded to oxygen, with hydrocarbon chains on both sides
• Properties of ketones


  • Similar to aldehydes - contain polar C=O bonds, boiling point lower than alcohol, higher than hydrocarbon, small ones soluble in water
• Carboxyl group

  Carbon double bonded to oxygen, with hydroxyl group (-OH) on one side
• Properties of carboxylic acids

  • Presence of C=O and -OH makes very polar, can form hydrogen bonds
  • Boiling point higher than hydrocarbon derivatives of same size
  • Small ones soluble in water, larger ones less soluble
  • Weak acids, react with bases and conduct electric current
• Ester group

  Carbon double bonded to oxygen, with oxygen single bonded to hydrocarbon chain on one side
• Properties of esters


  • Somewhat polar due to C=O, but cannot form hydrogen bonds
  • Boiling point lower than corresponding alcohol or carboxylic acid
  • Small esters soluble in water, larger ones less soluble
  • Volatile, create characteristic aromas
• Amide group

  Carbon double bonded to oxygen, with nitrogen on one side