module 4

• General formula: The simplest algebraic formula of a member of a homologous series e.g. for an alkane: CnH2n+2
• Structural formula: The minimal detail that shows the arrangement of atoms in a molecule e.g. for butane: CH3CH2CH2CH3 or CH3(CH2)2CH3
• Displayed formula: The relative positioning of atoms and the bonds inbetween
• Skeletal formula: The simplified organic formula, shown by removing hydrogen atoms from alkyl chains, leaving just a carbon skeleton and associated functional groups e.g. for butan-2-ol
• Alkyl group: Formula CnH2n+1
• Aliphatic: A compound containing carbon and hydrogen joined together in straight chains, branched chains or non-aromatic rings
• Alicyclic: Are aliphatic compounds arranged in non- aromatic

  rings with or without side chains
• Aromatic: A compound containing a benzene ring
• Saturated: Single carbon–carbon bonds only
• Unsaturated: The presence of multiple carbon–carbon bonds, at least one C=C double bond, a C≡C triple bond or an aromatic ring
• Define Homologous series

  A series of organic compounds having the same functional group

  but with each successive member differing by CH2
• Functional group

  An atom/group responsible for the characteristic reactions of a compound
• Structural isomer

  Compounds with the same molecular formula (1) but different structural formulae (1)
• Homolytic Fission

  The breaking of a covalent bond (1) where one electron from the bonding pair goes to

  each atom to form 2 radicals (1)
• Heterolytic fission

  The breaking of a covalent bond (1) where both electrons from the bonding pair goes to the same atom to form 2 ions (1)
• Radical

  A species with an unpaired electron (1)
• Curly arrow: Movement of an electron pair (1)
• Stereoisomers: Compounds with the same structural formula (1) but with a different arrangement in space (1)
• Electrophile: An electron pair acceptor (1)

  Nucleophile: An electron pair donor (1)