Organic chemistry

• Organic compounds


  Compounds that have carbon forming the backbone of the molecules
• Crude oil


  Found underground, result of Plankton being buried underwater a long time ago
• Hydrocarbons


  Molecules only made up of carbon and hydrogen atoms
• Alkanes


  • Chains of single covalently bonded carbon atoms surrounded by hydrogen atoms
  • Always twice as many hydrogens as carbons in a molecule plus another two on the ends
  • General formula: CnH2n+2
• Alkane names


  End with 'ane', beginning tells carbon chain length (meth-1, eth-2, prop-3, but-4, pen-5, hex-6, etc.)
• Fractional distillation of crude oil

  1. Heat to evaporate, rise up fractionating column

  2. Condense at different heights based on boiling points

  3. Collect different fractions (LPG, petrol, kerosene, diesel, heavy fuel oil)
• Alkane fractions


  • Shorter fractions more flammable
  • Longer fractions more viscous
• Alkenes


  Hydrocarbons with a carbon-carbon double bond
• Alkenes


  • Unsaturated, can react with bromine water to test for presence
  • Can be used to make polymers, unlike alkanes
• Cracking


  1. Breaking apart longer alkanes into shorter alkanes and alkenes

  2. Catalytic cracking at 550°C with zeolite catalyst

  3. Steam cracking at over 800°C with no catalyst
• Alcohols


  Organic compounds with an -OH functional group, names end in -ol
• Alcohol combustion


  1. Complete combustion with oxygen produces CO2 and H2O

  2. Incomplete combustion produces CO and H2O
• Carboxylic acids


  Organic compounds with a -COOH functional group
• Alcohol oxidation


  Oxidation without combustion produces a carboxylic acid
• Polymers


  Long chain alkanes made up of repeating sections from monomers
• Addition polymerization


  Monomers with double bonds join together
• Condensation polymerization


  Monomers with two functional groups (e.g. alcohol and carboxylic acid) join together, releasing water
• Amino acids


  Building blocks of proteins, have both amino (-NH2) and carboxyl (-COOH) functional groups
• DNA


  Large molecule that stores genetic code, made from two polymers of nucleotides in a double helix
• Starch


  Natural polymer made from glucose monomers
• Cellulose


  Natural polymer made from beta-glucose monomers