Burning fuels

• What do most fuels contain?

  carbon, hydrogen and some contain sulfur
• Combustion


  involves reactions of the elements in the burning substance with oxygen in the air , producing oxides
• What does the comubstion of hydrocarbon fuels release?

  energy
• What happens during combustion?

  the carbon and hydrogen in the fuels are oxidised
• What is produced after combustion?

  Oxides of each element in the burning substance
• What gases are released when a fuel burns?

  Carbon dioxide , Water vapour, Carbon monoxide, Sulfur dioxide, Oxides of nitrogen, particulates
• Carbon dioxide


  when enough oxygen is present ( complete combustion )
• Water vapour

  hydrogen oxide
• Carbon monoxide


  when there is not enough oxygen present ( incomplete combustion )
• Sulfur dioxide


  most fuels contain some sulfur
• Oxides of nitrogen


  formed at high temperatures ( in furnaces and engines ) because 78 % of the air is nitrogen gas
• particulates


  consisting of soot ( carbon ) and unburnt fuels . This happens when there is a limited amount of air , such as in an engine ( incomplete combustion ) .
• What causes acid rain?

  Sulfur dioxide and oxides of nitrogen
• How is acid rain harmful?

  can react with the stone and metal of structures such as buildings . It also can harm plant and animal life
• What does carbon dioxide cause?

  global warming
• How does carbon dioxide cause global warming?

  This is because it is a " greenhouse gas " which reduces the amount of heat lost from the Earth
• What does global warming and climate change cause?

  more extreme weather conditions such as flooding or droughts