Extracting Metals

HideShow resource information
  • Created by: beth
  • Created on: 31-12-12 14:29
View mindmap
  • EXTRACTING METALS
    • A METAL ORE is a rock which contains enough metal to make ETRACTION worthwile
    • Most metals need to be extracted using CHEMICAL REACTIONS by either REDUCTION  or ELECTROLYSIS
    • REDUCTION USING CARBON
      • Some metals can be extracted by reduction using CARBON
      • When an ore is reduced, OXYGEN is REMOVED
        • E.g. Iron Oxide + Carbon > Iron + Carbon Dioxide
          • 2Fe2O3 + 3C > 4Fe + 3CO2
      • The position of the metal in the REACTIVITY SERIES determines whether it can be extracted by REDUCTION WITH CARBON
        • Any element BELOW carbon can be extracted by REDUCTION USING CARBON
          • This is because carbon can only take oxygen away from metals that are LESS reactiove than itself
    • USING ELECTROLYSIS
      • ELECTROLYSIS is the BREAKING DOWN of a substance using ELECTRICITY
      • It requires a liquid to CONDUCT the ELECTRICITY called the ELECTROLYTE, which are often METAL SALT SOLUTIONS made from the ORE or MOLTEN METAL OXIDES
      • The ELECTROLYTE hs FREE IONS which CONDUCT the ELECTRICITY so the whole thing works
      • ELECTRONS are TAKEN AWAY by ANODE and GIVE AWAY by CATHODE. As ions GAIN/LOSE electrons, they become ATOMES/ MOLECULES and are released
      • Any element ABOVE carbon in THE REACTIVITY SERIES can be extracted using ELECTROLYSIS of MOLTEN COMPOUNDS
      • This process is much more EXPENSIVE than reduction using carbon as it uuses A LOT MORE ENERGY
      • Copper is PURIFIED by electrolysis even though it is quite EXPENSIVE because copper extracted by REDUCTION USING CARBON is IMPURE and so doesn'y CONDUCT electricity
    • COPPER ORES
      • COPPER ORES are in SHORT SUPPLY so scientists have found new methods the extrct copper
      • BIOLEACHING
        • Some bacteria ABSORB COPPER COMPOUNDS THEN PRODUCE SOLUTIONS CALLED LEACHATES, WHICH CONTAIN COPPER COMPOUNDS
      • PHYTOMINING
        • This involves growing plants in SOIL  containing coppper. Plants CAN'T USE/ GET RID of the copper so it gradually BUILDS UP in the LEAVES and can then be HARVESTED, FRIED or BURNED in a FURNACE
      • These have a much SMALLER IMPACT on the ENVIRONMENT but are SLOWER
    • IMPACTS
      • ADVANTAGES
        • USEFUL PRODUCTS can be made
        • Provides people with JOBS which brings money into the LOCAL ECONOMY
      • DISADVANTAGES
        • Causes NOISE
        • Permanently DAMAGES the LANDSCAPE
        • Loss of HABITATS

Comments

No comments have yet been made

Similar resources:

See all resources »See all resources »