Changing the way you learn

Making crude oil useful
1. Fossil Fuels
  1. Finite resources because they are no longer being made/are being made slowly
  2. Non-renewable resources- used up faster than they are being formed.
  3. Difficulties of crude oil; -readily extractable resources will be used in the future -finding replacements
2. Fractional distillation
  1. Crude oil is a mix of many types of oil, which are all 'hydrocarbons'
    1. Hydrocarbons- made up of molecules only with carbon and hydrogen in them
  2. Crude oil is heated at the bottom of a fractionating column
    1. Oil that doesn't boil sinks as thick liquid at the bottle- Bitumen.
      1. Has a very high boiling point
        Hard to break apart
  3. LPG - PETROL - PARAFFIN - DIESEL - HEATING OIL -FUEL OILS - BITUMEN
  4. Can be separated because the hydrocarbons in different fractions have different sized molecules.
    1. Intermolecular forces- forces between molecules and are broken during boiling
    2. Petrol- weak attractive forces and are easily separated. Less energy is needed and has a low boiling point because of this
3. Problems in extracting crude oil
  1. Can damage birds feathers and cause deaths.
  2. Oil producing nations can set high prices and cause problems for future supply
  3. Naphtha- high demand for use in medicines, plastics and dyes
Using carbon fuels
1. Choosing fuels
  1. Fossil fuels burning is increasing because populations are too
  2. Government is concerned because of the increasing carbon dioxide emissions that result from fossil fuels
  3. Countries with huge populations (China, India) are now using more fuel which means more gas emissions
  4. Can't be solved by one country alone, trying to cut carbon dioxide emissions in the next 15-20 years.
2. Combustion
  1. Burning hydrocarbons in air produces carbon dioxide and water.
    1. methane + oxygen = carbon dioxide + water
  2. Complete combustion- when a fuel burns in plenty of oxygen
    1. More energy is released during complete combustion than during incomplete combustion
      1. CH4 + 2CO2 = CO2 + 2H2O
  3. Incomplete combustion
    1. Carbon monoxide and soot is made
      1. fuel + oxygen = carbon monoxide + water
        or fuel + oxygen = carbon + water
        2CH4+3O2 = 2CO + 4H2O
        CH4 + O2 = C + 2H2O
Making Polymers
1. Hydrocarbons (Alkanes and Alkenes)
  1. Alkanes- 'Family' of hydrocarbons with single convalent bonds only. They are saturated
    1. Methane- CH4
      1. Ethane-C2H6
        Propane-C3H8
        Butane-C4H10
    2. Cn H2n+2
  2. Alkenes- 'Family' of hydrocarbons with double convalent bond between carbon atoms(two shared pair of electrons) Unsaturated
    1. Ethene- C2H4
      1. Propene- C3H6
        Butene- C4H8
    2. Bromine test-when added, turns colourless due to the new compound formed by an addition reaction - di-bromo compound
2. Polymerisation
  1. Addition Polymerisation- process in which many alkene monomers react to give a polymer. Needs high pressure and a catalyst
    1. Recognise by displayed formula by looking for; long chain, pattern repeating every two carbon atoms, two brackets at the end and an n after the brackets
    2. Involves the reaction of many unsaturated monomer molecules (alkenes) to form a saturated polymer.
  2. Displayed formula of an addition polymer can be constructed when the displayed formula of its monomer is given, and vise-versa
Clean Air
1. Clean Air
  1. Made up of 78% nitrogen, 21% oxygen and of the remaining 1% only 0.035% is carbon dioxide
    1. Carbon Dioxide has increased due to deforestation (less photosynthesis takes place) and increased population, as the energy requirements increase
2. The atmosphere
  1. Gases escaping the interior of the Earth formed the original atmosphere. Plats could photosynthesise which removed carbon dioxide and added oxygen, so it could reach its current level
  2. Gases come from the centre of the Earth through volcanoes in a process called degassing.
    1. One theory by scientists said that the atmosphere was originally in water vapour and carbon dioxide. This then condensed to form oceans and carbon dioxide dissolved in it. Nitrogen increased and slowly overtime some was removed.
    2. Another is that over time, organisms that could photosynthesise evolved and converted carbon dioxide and water into oxygen. As the percentage increased, the carbon dioxide decreased and todays levels were reached.
3. Pollution control
  1. Sulfur Dioxide is pollutant that can cause difficulities for people with asthma. Also dissolve in water to form acid rain.
  2. Catalytic converter in car- changes carbon monoxide to dioxide
  3. In a catalytic converter- a reaction between nitric oxide and carbon monoxide takes place on the surface. Two gases are formed and are natural components of air- nitrogen and carbon dioxide
    1. 2CO + 2NO = N2 + 2CO2
Designer Polymers
1. Breathable polymers
  1. Nylon- tough, lightweight, keeps water out, keeps uv light out but doesn't let water vapour through. Means that sweat condesnses and makes the wearer wet and cold inside the jacket
  2. GORE-TEX is waterproof and breathable. It's made of PTFE- the holes are too small for water to pass through but not big enough to pass through. Too fragile on it's own so it is laminated onto nylon to produce a strong fabric.
2. Disposing of Polymers
  1. Disposal of non-biodegradable polymers means landfill sites get filled quickly.
  2. Disposal by burning waste plastics makes toxic gases.
  3. Disposal by burning or using landfill sites wastes the crude oil used to make the polymers.
3. Stretchy polymers and rigid polymers
  1. Held together by strong covalent bonds
  2. Properties of plastics can be related to simple models of structure.
    1. Plastics that have weak intermolecular forces between polymers have low melting points and can be stretched easily as the polymer molecules can slide over each other.
    2. Plastics that have strong forces between the polymers have high melting points, they can't be stretched and are rigid
Cooking and food additives
1. Proteins and Carbohydrates
  1. Protein molecules in eggs and meat permanently change shape when they're cooked
    1. This is called Denaturing
    2. Potatoes (Carbohydrates) are easier to digest if it's cooked because; - the starch grains swell up and spread out/the cell walls rupture resulting in the loss of their rigid structure and a softer texture is produced.
2. Baking Powder
  1. Sodium Hydrogencarbonate
    1. When it's heated it decomposes to give carbon dioxide
      1. Sodium Hydrogencarbonate = sodium carbonate + carbon dioxide + water
        2NaHCO3 = Na2CO3 + CO2 + H2O
3. Emulsifiers
  1. Molecules that have a water loving part and an oil or fat loving part
    1. Oil/fat loving part goes into the fat droplet
  2. Help to keep oil and water from separating
    1. Water loving part end bonds to the water molecules
      1. The fat loving part end bonds to the oil or fat molecules
        Water loving part end is attracted to the water molecules which surround the oil, keeping them together
Smells
1. Esters
  1. Alcohol + acid = ester + water
  2. Experiment; Acid is added to the alcohol and heated. The condenser stops the gas from escaping and helps it cool down so it can react more. The condenser allows the reaction to go on for longer..
2. Perfume properties
  1. Evaporate easily, so that the particles can be smelt
  2. Be non-toxic so it doesn't posion you
  3. Not react with water so it doesn't react with sweat
  4. Non-irritant so doesn't harm the skin
  5. Be insoluble in water so it can't be washed off easily
3. Solutions
  1. A solution is a mixture of solvent and solute that doesn't spread out
  2. Esters can be used as solvents
4. Particles
  1. Evaporation of perfume can be explained by the kinetic theory.
    1. In order to evaporate, particles of a liquid need sufficient kinetic energy to overcome the forces of attraction to other molecules in the liquid
      1. Only weak attractions exist between particles of the liquid perfume so it's easy to overcome these attractions as they have sufficient kinetic energy
  2. Water will not dissolve nail varnish colours because the attraction between the water and water molecules is stronger than the attraction between the water and nail varnish molecules.
Paints and Pigments
1. Colloids
  1. Paint is a colloid where the particles are mixed and dispersed with particles of a liquid but are not dissolved
  2. The components of a colloid won't separate because the particles are scattered throughout the mixture
2. Paint drying
  1. Emulsion paints are water based paints that dry when the solvent evaporates
  2. Oil paints dry because the solvent evaporates or the oil is oxidised by atmospheric oxygen
3. Thermochromic pigments
  1. Change colour at different temperatures. Used as thermometers/cups/electric kettles/baby spoons or bath toys.
  2. Can be added to acrylics to make even more colour changes.
4. Phosphorescent pigments glow in the dark because they store and absorb energy and they release energy as light over a period of time. They are much more safer than the older alternative radioactive paints

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	Created by georgia.somerville over 10 years ago