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• Crude oil is a finite resource found in rocks
• Crude oil is the remains of an ancient biomass consisting mainly of plankton that was buried in mud
• Mixture

  2 or more elements that are not chemically combined
• Alkenes


  Hydrocarbons with the functional group C=C

  
• The chemical properties of each substance in the mixture are unchanged
• Separating substances in the crude oil mixture

  Physical methods including distillation
• Addition polymerisation

  1. Alkenes can be used to make polymers such as poly(ethene) and poly(propene)

  2. Many small molecules (monomers) join together to create very large molecules (polymers)
• First 4 alkenes


  • Ethene
  • Propene
  • Butene
  • Pentene
• Most of the compounds in crude oil consist of molecules made up of hydrogen and carbon only (hydrocarbons)
• Repeat unit

  Has the same atoms as the monomer because no other molecule is formed in the reaction
• Unsaturated carbons

  • Can be represented in the following forms:
• Most of these saturated hydrocarbons are alkanes
• When drawing a polymer, remember to draw the bonds coming off the Cs out the brackets and the little 'n' (means there are large numbers of these molecules joined together)
• Alkenes react with oxygen in combustion reactions in the same way as other hydrocarbons, but they tend to burn in air with smoky flames because of incomplete combustion (meaning carbon or carbon monoxide is formed (CO))
• Hydrocarbons

  Have the general formula: CnH2n+2

  
• Condensation polymerisation


  1. Involves monomers with two functional groups

  2. When they react, they join together, usually losing small molecules such as water, and so the reactions are called condensation reactions

  3. Simplest polymers are produced from two different monomers with two of the same functional groups on each monomer
• Reactions of alkenes


  React with hydrogen, water and the halogens, by the addition of atoms across the carbon-carbon double bond so that the double bond becomes a single carbon-carbon bond
• Polyester

  • 1 monomer with 2 carboxylic acid functional groups and 1 monomer with 2 alcohol functional groups
• First 4 alkanes


  • Methane
  • Ethane
  • Propane
  • Butane

  
• Fractional distillation


  Oil is heated in the fractionating column and the oil evaporates and condenses at different temperatures
• Amino acids

  • They have two different functional groups in a molecule (an amine group and a carboxylic acid group)
  • They react by condensation polymerisation to produce polypeptides
  • Different amino acids can be combined in the same chain to produce proteins
• In each reaction with hydrogen, water and halogens: the C=C bond is broken to form a C-C bond, the compound added splits into two groups and the two groups are added to the 2 different carbons in the C=C bond (each group can be added to either carbon), H2 splits into 2 H's, H2O splits into a H and an OH, Br2 splits into 2 Br's (same for Cl2 or I2)
• The many hydrocarbons in crude oil can be separated into fractions each of which contains molecules with a similar number of carbon atoms
• Alcohols

  Contain the functional group -OH
• DNA (deoxyribonucleic acid)

  • A large molecule essential for life- it encodes genetic instructions for the development and functioning of living organisms and viruses
  • Most molecules are two polymer chains, made from four different monomers called nucleotides, in the form of a double helix
• The fractionating column works continuously, with heated crude oil piped in at the bottom
• First 4 alcohols

  • Methanol
  • Ethanol
  • Propanol
  • Butanol

  
• Other naturally occurring polymers important for life

  • Proteins (monomer= amino acid)
  • Starch (monomer= glucose)
  • Cellulose (monomer= glucose)
• The various fractions are constantly tapped off at the different levels where they condense
• Fuels produced from crude oil fractions

  • Petrol
  • Diesel oil
  • Kerosene
  • Heavy fuel oil
  • Liquefied petroleum gases
• Alcohols burn in air, which produces carbon dioxide and water
• Alcohols dissolve in water to form a neutral solution (has a pH of 7)
• Materials produced by the petrochemical industry

  • Solvents
  • Lubricants
  • Polymers
  • Detergents
• Alcohols react with sodium to produce hydrogen and a salt (e.g. C2H5ONa- the H has been given off and Na has been added)
• The vast array of natural and synthetic carbon compounds occur due to the ability of carbon atoms to form families of similar compounds
• Alcohols react with oxidising agents to form carboxylic acids

  
• Viscosity

  How runny a hydrocarbon is
• Uses of alcohols

  Methanol: chemical feedstock, in anti-freeze, to make biodiesel

  Ethanol: the main alcohol in alcoholic drinks, used as a solvent and fuel

  All 4: can be used as fuels
• Shorter the hydrocarbon molecules

  Less viscous it is
• Longer the hydrocarbon molecules


  More viscous it is