2.2

• What is a fuel?

  A substance with stored energy that can be released relatively easily for use of heat or power.
• What are the use of fuels by society?

  • Local level (the type of petrol used in your car)
  • National level (whether Australia’s use of energy resources is sustainable)
  • Global level (whether the use of fossil fuels – coal, oil and natural gas – is contributing to the enhanced greenhouse effect) 
• What are non - renewable resources?

  • Resources that are used faster than they can be replaced
  • Examples: Coal, Oil and Natural Gas 
• How are fossil fuels formed?

  • Coal, oil and natural gas were formed from ancient plants, animals and microorganisms.
  • The organic matter still retains some of the chemical energy the plants originally accumulated by carrying out photosynthesis
  • Chemical energy in fossil fuels can be considered to be trapped solar energy
• What happens as the wood and other plant material is converted into coal?

  The carbon content increases and the portion of hydrogen and oxygen decreases
• What is renewable energy?

  Energy that can be obtained from natural resources that can be constantly replenished.
• What are biofuels/biochemical fuels?

  • Fuels derived from plant materials, such as grain, sugar cane and vegetable waste and vegetable oils
  • often carbon neutral as CO2 emissions are used up by plant matter during photosynthesis
• What are the three main biofuels?

  • Bioethanol
  • Biogas
  • Biodiesel
• Which fuels are carbon-based?

  • Crude Oil
  • Coal
  • Natural Gas
  • Biodiesel
  • Petrol
  • Biogas
  • Diesel
  • E10
  • Hydrogen
• What is coal?

  • Coal is most efficient source as it has the lowest water content
  • Energy is used to evaporate the water
  • Organic dead matter (sedimentary rock) which is condensed through high heat/pressure over a long period of time (therefore non – renewable)
  • extracted via mining

   
• What is crude oil?

  • a mixture of hydrocarbons
  • the useful fuels within crude oil are extracted via fractional distillations
  • used for transport and heating
  • extracted via fracking
• What is a natural gas (coal seam gas)?

  • a fossil fuel found deep in the earth’s crust, made up mainly of methane with small amount of ethane and propane
• Where can natural gases be found?

  • coal deposits where it is bonded to the surface of coal
  • component of petroleum
  • trapped between layers of rocks
• What is a bioethanol?

  • Ethanol is made by fermenting the sugar and starch components of plants using yeast
  • replaces crude oil 
• What is biogas?

  • a mixture of gases produced by the decomposition of organic matter in the absence of oxygen
  • can be used for heating
  • manure/farm waste is inserted into a digester containing anaerobic bacteria
  • useful on farms as the farm waste can be used as a fuel minimising transport needed
• What is a biodiesel?

  • A fuel derived from plant or animal matter, consisting of long – chain alkyl esters (trans – esterification)
  • Made by reacting triglycerides with an alcohol
  • Due to polarity of the ester, it attracts water which prevents efficient combustion
  • can attract water which reduces efficiency of engines
  • it is made from animal and vegetable fat, its production may prioritise food production leading to food shortages 
• What is trans – esterification?

  A process in which triglyceride reacts with an alcohol to form esters