C3

HideShow resource information
View mindmap
  • C3
    • % Yield
      • May be low due to...
        • Filtering
        • Evaporating
        • Transferring liquids
        • Not all reactants react to make product
      • Should be as high as possible in industrial process
        • Reduces process cost
        • Reduces waste of reactants
        • No need to recycle unreacted materials
      • (Actual yield / predicted yield) * 100%
      • 100%: all reactants are converted to product with no losses in process
      • 0%: no product formed or collected
    • Atom Economy
      • (Mr of desired product / total Mr of products) * 100%
      • 100%: all reactants have changed into wanted product
      • Low %: only some atoms in reactants have changed into wanted product
    • Calorimetry
      • Fair test
        • Water volume
        • Start temp.
        • Temp. change
        • Draughts
        • Height of flame from calorimeter
        • Height of flame/length of wick
        • Stirring to distribute heat
      • Reliability
        • Repeat
        • Identify + ignore anomalies
      • Exothermic: Energy emit-ted, temp. rise, bonds made, products have less energy than reactants
      • Endothermic: Energy absorbed, temp. falls, bonds break, atoms move apart, products have more energy than reactants
      • Equations
        • Energy transferred (J) = water mass (g) * 4.2 * temp. rise (C)
        • Energy output (J/g) = energy released (J) / fuel mass burnt (g)
    • Allotropes of C + nano-chemistry
      • Graphite
        • Giant molecular structure, lots of energy needed to separate atoms as covalent bonds are strong + there are many covalent bonds (making it hard with very high melting + boiling point)
          • Diamond
            • Lustrous, transparent, insoluble in water, reflects light (so sparkles)
            • Uses: drills, jewellery, cutting tools
            • No free electrons/ionso doesn’t conduct electricity
        • Lustrous, insoluble in water, black + opaque
        • Uses: pencil lead, lubricants
        • Each carbon atom is covalently bonded to 3 other carbon atoms
        • Contains layers of carbon atoms that slide over each other easily as there are only weak forces between them so it’s slippery
        • Contains delocalised electrons which carry charge, allowing it to conduct electricity
      • Diamond
        • Lustrous, transparent, insoluble in water, reflects light (so sparkles)
        • Uses: drills, jewellery, cutting tools
        • No free electrons/ionso doesn’t conduct electricity
      • Fullerenes + Nanotubes
        • Buckminster fullerene: C60, hollow sphere
        • Nanotubes reinforce graphite in tennis rackets as they are very strong, used as semiconductors in electrical circuits
        • Structure allows it to transport drugs in body (a molecule of drug can be placed inside nanotube cage) + can increase therapeutic activity of some fullerene-based drugs
        • Giant molecular structure, high melting + boiling point
        • Nanotubes: massive surface area so spreading catalyst on surface increases its effectiveness + activity
    • Batch + Continuous
      • Continuous
        • Advantages
          • High prod. rate
          • Rare shut-down time
          • Small workforce needed
          • Ease of automation: easy
        • Dis-advantage: high factory equip. cost
        • Large scale prod. e.g. NHO3
      • Batch
        • Advantage: low factory equip. cost
        • Dis-advantages
          • Low prod. rate
          • Shut-down time: often
          • Large workforce needed
          • Ease of auto-mation: hard
        • Small scale prod. e.g. drugs
      • Drug development
        • High cost because...
          • Marketing
          • Time taken for development
          • Labour costs
          • Research + testing
          • Legal costs in licensing new drug
          • Energy costs
          • Raw materials
        • Drug companies must balance...
          • Pay-back time length
          • Expected demand for new drug
      • Establishing purity
        • Thin layer chromato-graphy
        • Greater impurity: bigger difference between true melting + boiling point

Comments

No comments have yet been made

Similar Chemistry resources:

See all Chemistry resources »See all C3 resources »