Paper 2

• What is difference between melting and boiling points of pure and impure substance?

  Pure- sharp/ one specific temp

  Impure- broad/ occurs across a range of temp
• What is a formulation?

  Mixture designed for a specific purpose
• Example of formulations:

  • Fuels, paint, foods, alloys
• How is Rf caluclated?

  distance moved by substance/ distance moved by solvent
• How do you test for hydrogen?

  . Hold a lighted splint near gas

  ~>Will hear a squeaky pop
• How do you test for oxygen?

  . Hold glowing splint near gas

  ~> splint re-lights
• How do you test for carbon dioxide?

  . Bubble gas through limewater

  ~> Limewater will turn milky
• How do you test for chlorine?


  . Hold a piece of damp litmus paper near gas

  ~> Bleaches litmus paper
• How is crude oil formed?

  Over millions of years from remains of ancient biomass
• Products of cracking:

  . Short chain alkanes and alkenes
• What are alkenes used for?

  Formation of polymers
• How did the oceans form?

  Water vapour condensing as the earth cooled
• The amount of carbon dioxide in atmosphere has decreased to todays levels by:

  • Dissolved in oceans
  • Photosynthesis
  • Converted to fossil fuels
  • Precipitated in ocean as sediments to form rocks
• What is the current composition of the atmosphere?

  80% nitrogen , 20% oxygen and trace amounts of carbon dioxide, water vapour and noble gases
• What type of radiation do greenhouse gases absorb?

  Longer wavelength infrared radiation
• What is carbon footprint?

  The amount of carbon a product, process or person releases into the atmosphere
• How is carbon monoxide formed- what danger is it associated with?

  Incomplete combustion; colourless and odourless toxic gas
• How are PARTICULATES formed- what rangers are associated?

  Incomplete combustion; potential to cause cancer
• Different alkanes in crude oil can be separated by:

  • FRACTIONAL DISTILLATION
• Using Earth’s Resources:

  . Natural resources

  • Wood ( finite resource)
  • Rubber
  • Crude oil/ gas
  • Metal‘ in earths crust
  • Water
• Using Earth’s Resources:

  . Man Made resources

  • Plastic
  • Gas
  • Paper
  • Steel
• What are biofuels?


  Renewable fuels made from organic matter, such as plants or animal waste.
• What is an ore?

  Rock containing enough metal to be ECONOMICALLY worth extracting
• Extracting metal from their ores are expensive:

  • High temperature and electricity are used which requires a lot of energy
• ALL METALS ARE FINITE:

  • We get out metals from ores in the ground
• Anything that is not reused or recycled ends up in landfill
• Life Cycle Assessments:

  Works out total environment impact of each of the stages of a products life
• Life Cycle Assessments STAGES:

  1. Extracting and processing raw materials
  2. Manufacturing and packaging product
  3. Using and reusing product
  4. Disposing of product

  . Can have NEGATIVE environmental impacts
• Disadvantages of extracting metal from the ground:

  • Large amounts of waste in landfill
  • Destruction of habitat
  • Noise and dust pollution from machines