C1

C1

1. Fundamental ideas

   • All substances are made from atoms
     • Atom
       • The smallest part of an element that can still be recognised as the element
   • Element
     • Shells
       • Electron
         • -
           • Equal number
     • Nucleus
       • Proton
         • +
           • Equal number
       • Neutron
         • 0
   • • Section of the periodic table - image from google search - GCSE periodic table

2. Limestone

   • • GCSE AQA Chemistry textbook image
   • • GCSE AQA Chemistry Textbook image
     • To make lots of CaO it is done in a
       • Lime kiln
         • Put crushed limestone in
         • Heat strongly with hot air
         • Waste products (CO₂) leave out the top
     • Rotary kiln
       • Heated in a rotating drum
       • Helps to decompose quickly
       • Limestone throughly mixed with hot air
   • Calcium carbonate
     • Can be quarried and used as building materials
     • Decomposed by heating
       • Thermal decomposition
       • Make:
         • Calcium oxide
           • Reacts with water
             • Calcium hydroxide
               • Alkali
                 • Used to neutralise acids
         • Carbon dioxide
           • Limewater
             • Cloudy
             • CaOH in water reacts with CO₂
           • Carbonates react with acids to produce
             • CO₂
             • Salt
             • H₂O
     • Limestone is damaged by:
       • Acid rain
   • Limestone
     • Heated with clay to make
       • Cement
         • Mixed with sand to make
           • Mortar
         • Mixed with sand and aggregate to make
           • Concrete

3. Metals

   • Ore
     • Contains enough metal to make it economical to extract the metal
     • Mined and may be concentrated before the metal is extracted and purified
   • Unreactive metals such as gold are found in the Earth as the metal itself
     • But most as found as compounds that require chemical reactions to extract the metal
   • Extracted
     • Metals less reactive than C can be extracted from their oxides by reduction
     • Metals more reactive than C can be extracted by copper-rich ores by smelting
       • Copper can be purified by electrolysis
         • Supply is limited
   • New ways of extracting copper from low-grade ores
     • Traditional mining impacts
     • Phytomining
       • Uses plants to absorb metal compounds and the plants are burned to produce ash that contains metal compounds
     • Bioleaching
       • Uses bacteria to produce leachate solutions that contain metal compounds
     • Copper can be obtained from solutions of copper salts by electrolysis or displacement using scrap iron
   • Cannot be extracted from their oxides by reduction with C
     • Too expensive because
       • Too many stages in the process
       • Large amount of energy needed
     • Titainium
       • Denser than Al
       • Don't corrode
       • Light
       • Strong
       • High melting point
       • C reacts making it brittle
     • Aluminium
       • Don't corrode
       • Good heat conductor
       • Light
       • Strong
       • Malleuble
       • Shiny
       • Silvery
   • We should recycle metals because extracting them uses limited resources and is expensive in terms of energy and effects on the environment
   • Alloys
     • • Google searched image - Blast Furnace
     • Iron from the blast furnace contains about 96% iron
       • Impurities make it brittle so it has limited uses
     • Steels are alloys
     • Low-carbon steels are easily shaped
     • High-carbon steels are hard
     • Stainless steels are resistant to corrosion
     • Pure Cu, Au, Fe are too soft for many uses
       • Alloyed to make them harder
   • Transition metals - Cu
     • Good conductor of heat and electricity
     • Not react with water

4. Crude oil

   • Is a mixture of a very large number of compounds
     • Can be separated using distillation
   • Hydrocarbons
     • Most are saturated, AlkAnes
       • CnH₂n+2
     • High boiling point
     • Low viscosity
     • Flammable
     • Hydrocarbon fuels
       • Most fuels including coal, contain carbon and/or hydrogen may also contain some sulfur
         • Gases released into the atmosphere
           • CO₂
           • H₂O vapour
           • CO
           • SO₂
           • Particulates
           • Oxides of nitrogen
       • The combustion of hydrocarbon fuel releases energy
         • During combustion the carbon and hydrogen in the fuels are oxidised
       • Sulfur dioxide and oxides of nitrogen
         • Acid rain
         • Sulphur can be removed from the fuels before they are burned e.g. in vehicles
         • Can be removed from the waste gases after combustion e.g. power stations
       • Carbon dioxide
         • Global warming
       • Solid particulates
         • Global dimming
       • Biofuels
         • Biodiesel
         • Bioethanol
         • Are produced from plant material
         • Ethical issues
           • More people are needed to produce these fuels
           • Increased income for farmers
           • Reduce fuel prices due to the limit in demand for fossil fuels
   • May be separated into fractions
     • By allowing it to evaporate and then condense at a number of different temperatures
       • Fractional distillation
   • More about crude oil
     • Cracking
       • Hydrocarbons can be cracked to produce smaller more useful molecules
       • Involves heating hydrocarbons to vaporise them
       • The vapours are either passed over a
         • Hot catalyst
         • Mixed with steam and heated to a very high temperature
       • So thermal decomposition can occur
       • The products include
         • AlkAnes
         • Alkenes
           • CnH₂n
           • React with bromine water
             • Colourless
         • Some products are used as fuel
     • Polymers
       • Polymerisation
         • Small chain monomers
         • Long chain molecules - Polymers
       • • AQA image
       • Have useful applications
         • Shape memory polymers
         • Waterproof coatings
       • Non-biodegradable
         • Not broken down by microbes
         • Problems with waste disposal
         • Plastic bags are being made from polymers and cornstarch so that they can break down more easily
           • Been developed
     • Ethanol
       • Can be produced by hydration of ethene with steam in the presence of a catalyst
       • Fermentation with yeast using renewable resources
         • Sugar -> carbon dioxide + ethanol

5. Plant oils

   • Vegetable oil
     • Rich in oils that can be extracted by
       • Nuts
       • Seeds
       • Fruit
       • Pressing
       • Distillation
       • Water and other impurities are removed
     • Provide lots of energy
     • Lots of nutrients
     • Higher boiling point than water
       • Cook foods at higher temperatures
       • Quicker cooking
       • Different flavours
       • Increases the energy released when it's eaten
   • Emulsions
     • • Chemistry GCSE AQA Textbook image page 91
     • Oils do not dissolve in water
       • Used to produce emulsions
         • Emulsions are thicker than water
     • Provide better
       • Texture
       • Coating ability
       • Appearance
     • Hydrophobic
       • 'tail'
       • Long hydrocarbon chain
       • Dissolve in oil
         • Tiny droplets
     • Hydrophillic
       • 'head'
       • Carry a charge
     • Charged by the 'heads'
       • Tiny oil droplets repel each other
         • They spread out throughout
   • Saturated and unsaturated oils
     • Vegetable oil
       • Hardened
         • Reacting with hydrogen
           • Adds the C+C bonds
         • Nickel catalyst
         • 60˚C
         • They have higher melting points
           • Solids at room temperature
           • Useful as spreads
       • Unsaturated
         • C=C
         • Detected using bromine water

6. Earth and atmosphere

   • Earth
     • Crust
       • Between 5km and 50km
         • Average 6km thick under the oceans
         • About 35km under continental areas
       • Solid rock
     • Core
       • Inner
         • Solid rock
         • 1,300km
       • Outer
         • Liquid iron and nickel (metal)
         • 2,200km
     • Mantle
       • 2,850km
       • Behaves like a solid but is able to flow really slowly - liquid rock
     • Atmosphere
       • 80% of the air in our atmosphere lies within 10km of the surface
         • The atmosphere has been the same for the last 200 million years
       • Nitrogen
         • 78%
       • Oxygen
         • 21%
       • Carbon dioxide
         • 0.04%
       • Nobel gases
         • Ar 0.9%
       • Water vapour
         • Condensed to form the oceans
       • First billion years
         • Intense volcanic activity
           • Released gases which formed the early atmosphere
       • Plants and algae produced the oxygen that is now in the atmosphere
       • CO₂
         • CO₂ has become locked up in sedimentary rock
           • As carbonate and fossil fuels
             • Burning fossil fuels releases it back into the atmosphere
         • Oceans act as a reservoir for CO₂
           • Increased amounts of CO₂ absorbed affect the marine environment
       • Air is a mixture of gases with different boiling points and can be fractionally distilled to provide a source of raw materials used in a variety of industrial processes
     • Theories
       • 1
         • Mainly CO₂
         • Little or no O₂
         • Like Venus or Mars today
         • Water vapour
         • Small proportions of methane and ammonia
       • 2
         • Miller Urey
           • Interaction between
             • Hydrocarbons
             • Lightening
             • Ammonia
           • Amino acids
           • Invalid because there was no O₂, and it was thought that O₂ was there
   • Tectonic plates
     • The earth's crust and the upper part of the mantle are cracked into large pieces
     • The movements can be sudden and disastrous
     • Occur at boundaries between tectonic plates
       • Earthquakes
       • Volcanic eruptions
   • Convection currents
     • Within the mantle
     • Heat released by
       • Natural radioactive processes
     • Causes the plates to move
       • A few centimetres a year

Images and files in the map