Organic Chemistry

Organic Chemistry Introduction

  • Organic chemistry focuses on the structure, properties, composition, reactions, and synthesis of organic compounds that by definition contain carbon atoms.
  • Carbon atoms can form strong covalent bonds with other carbon atoms and elements such as hydrogen, oxygen, and nitrogen, resulting in a vast array of compounds.

Hydrocarbons

  • Hydrocarbons are compounds made up of carbon and hydrogen atoms.
  • They can be either saturated (single carbon-carbon bonds) or unsaturated (double or triple carbon-carbon bonds).
  • Alkanes are saturated hydrocarbons with the general formula CnH2n+2, they are considered relatively unreactive due to single bond character.
  • Alkenes are unsaturated hydrocarbons with one or more carbon-carbon double bonds. Their general formula is CnH2n.

Reactions of Hydrocarbons

  • Hydrocarbons can undergo various reactions including combustion, substitution and addition reactions.
  • Combustion is a reaction with oxygen, producing carbon dioxide and water.
  • Substitution reactions involve replacing a hydrogen atom in an alkane with another atom or group of atoms.
  • Addition reactions are characteristic of unsaturated hydrocarbons (alkenes), where the double bond ‘opens up’, allowing new atoms to join the molecule.

Functional Groups and Homologous Series

  • A functional group is an atom or group of atoms within a molecule that shows a characteristic set of physical and chemical properties. Functional groups include alcohols, carboxylic acids, and halogenoalkanes.
  • A homologous series is a series of compounds of the same family, with the same general formula, behaving in a similar chemical manner due to the presence of the same functional group.

Alcohols, Carboxylic Acids, and Halogenoalkanes

  • Alcohols contain the functional group -OH and their general formula is CnH2n+1OH.
  • They can undergo combustion, oxidation and substitution reactions.
  • Carboxylic acids contain the functional group -COOH.
  • They exhibit properties of both acids and alcohols.
  • Halogenoalkanes contain a carbon-halogen bond. They can undergo substitution and elimination reactions.

Isomers

  • Isomers are compounds that have the same molecular formula but different structural formulae.
  • Isomerism occurs due to the possibility of branching in carbon chains.

Nomenclature

  • Nomenclature in organic chemistry is based on a specified set of rules by the IUPAC for naming organic compounds.
  • Learning this systematic method of naming compounds can simplify otherwise complex structures.