C1

C1

1. Pollutants

   • Chemicals that harm the environment and your health
   • Burning fossil fuels releases them
   • Acid rain
     • Rivers become too acidic and organisms die
       • Affects food chains and natural resources
   • Measure pollutants by ppb (parts per billion)
     • Repeat measurements to calculate a mean
   • Can't disappear so cause environmental problems
     • Particulate carbon is deposited on surfaces such as stone buildings
   • Produce too much carbon dioxide
     • Not all used up naturally
     • Greenhouse gas so contributes to global warming
   • Sulfur dioxide and nitrogen dioxide
     • React with water to produce acid rain
     • Cause and effect relationship seen in laboratory
       • Burn sulfur in oxygen
         • Dissolve gas in water
           • Produces strongly acidic solution

2. Atmosphere

   • Early atmosphere created by volcanic activity
     • Consisted of carbon dioxide and water vapour
   • Water vapour condensed to form oceans
   • Simple photosynthetic organisms evolved, adding oxygen and removing carbon dioxide
   • Carbon dioxide removed from dissolving in oceans, forming sedimentary rocks and fossil fuels

3. Chemicals

   • Properties of compounds are very different to properties of the elements
   • Reactions
     • Joined atoms separated
     • Separate atoms joined
     • Joined atoms separated then joined again differently
     • Mass is conserved as reaction never loses mass

4. Combustion

   • Fuel reacts with oxygen to release energy
     • Type of oxidation
   • Complete combustion
     • Enough oxygen present for fuel to burn completely
     • Hydrocarbons
       • Methane
         • Methane + oxygen = carbon dioxide + water
       • Only consist of hydrogen and carbon
       • Produce carbon dioxide and water when burned in air
   • Incomplete combustion
     • Fuel burns when there's not enough oxygen
     • Carbon particulates or carbon monoxide may be produced
       • Methane + oxygen = carbon + water
       • Methane + oxygen = carbon monoxide + water
     • Occurs in car engines
     • Coal contains sulfur
       • Produces sulfur dioxide when burnt
   • Nitrogen
     • High temperatures in car engines cause nitrogen to react with oxygen
       • Produces nitrogen monoxide
         • Nitrogen + oxygen = nitrogen monoxide
         • Then oxidised to form nitrogen dioxide
           • Nitrogen monoxide + oxygen = nitrogen dioxide

5. Pollution

   • Power stations
     • Use less electricity
     • Remove sulfur and toxic chemicals from fossil fuels before burning
     • Use sustainable resources e.g. Hydroelectricity energy
     • Remove sulfur dioxide from chimney gases
       • "Wet scrubbing" with spray of calcium oxide and water or seawater
   • Car pollution
     • Low-sulfur fuel with modern fuel-efficient engine
     • Legal limits for exhaust emissions enforced by MOT tests
     • Use public transport
     • Cars use "catalytic converters"
       • Reduce carbon monoxide and nitrogen monoxide in engine exhaust gases
       • Carbon monoxide + oxygen = carbon dioxide
       • Reduce emissions by burning fewer fuels
         • Very hard as the world has a growing population
       • Nitrogen monoxide + oxygen = nitrogen and carbon dioxide

Bilder und Dateien der Mindmap