chem

• Alkanes


  Saturated hydrocarbons
• Alkenes


  Unsaturated hydrocarbons
• Homologous series


  Organic molecules grouped together
• Homologous series


  • Each member differs from the previous by a CH2 unit
  • All members have similar chemical properties (reactivity) but different physical properties (boiling point, melting point etc.)
• Types of hydrocarbons


  • Saturated hydrocarbons
  • Unsaturated hydrocarbons
• Empirical formula


  Simplest ratio of atoms in a compound
• Molecular formula


  The actual number of atoms of each element in a molecule
• Structural formula


  Shows the location of atoms in a compound
• Semi-structural formula


  Shows atoms connected to each carbon but do not show bonds
• As the size of alkanes increase

  The boiling point increases
• Dispersion forces


  Intermolecular forces that increase with increasing molecular size
• Hydrocarbons do not dissolve in water
• Hydrocarbons are less dense than water and float on water
• Combustion reaction


  CO2 (g) and H2O (l) are the only products in a complete combustion
• Substitution reaction


  A reaction where one atom of an organic molecule is replaced by another atom (or group of atoms)
• Addition reaction


  A reaction involving the addition of a small molecule (H2, Cl2, Br2) across a C=C double bond
• Haloalkanes


  Organic molecules that contain at least one halogen
• Dipole-dipole attraction


  Intermolecular forces present in haloalkanes due to the electronegativity of the halogen
• Haloalkanes have higher boiling points than their corresponding alkanes and alkenes
• Haloalkanes are reactive due to the electronegativity of the halogen
• IUPAC nomenclature


  The standard for naming organic molecules worldwide
• Parent chain


  The longest carbon chain in a hydrocarbon
• Stem names for alkanes


  • Meth-
  • Eth-
  • Prop-
  • But-
  • Pent-
  • Hex-
  • Hept-
  • Oct-
  • Non-
  • Dec-
• Alkenes


  Unsaturated hydrocarbons with at least one carbon to carbon double bond
• Haloalkanes


  Organic molecules with at least one halogen atom
• Alkyl groups


  Side groups/side chains/branches composed of carbon and hydrogen atoms
• Structural isomers


  Molecules with the same molecular formula but different atomic arrangements
• Alcohols


  Hydrocarbons that contain a hydroxyl (-OH) group
• Carboxylic acids


  Compounds characterised by a carboxyl group (-COOH)
• Carboxylic acids are weak acids often found in food to give a sour taste
• Crude oil supplies fuels for energy and feedstock for making plastics, solvents, paints, dyes, and pharmaceuticals
• Biomass


  Organic material that comes from living organisms such as plants, animals and microorganisms
• Plant-based biomass


  • Corn
  • Sugar cane
• Ethanol can be produced from


  • Crops with high glucose content
  • Fossil fuels
• Morphine is an important therapeutic for pain relief and is produced from opium poppy plants
• Advantages and disadvantages of using plant-based biomass


  • (not provided in the material)