Section N notes

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Carbon monoxide is poisonous

Fossil fuels burnt - produce CO

Posionous gas. Combines haemoglobin in red blood cells , it prevents them from carrying oxygen

CO released in Car Emissions. Most modern cars are fitted with cataltic converters that turn the CO into CO2 , decreasing the amount of CO thats released into the atmosphere

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acid rain causes sulphur dioxide

burning fossil fuels release SO2

SO2 gas comes from sulphur impurities in crude oil

SO2 gas mixed with rain clouds form  H2SO4

falls as acid rain

power stations , combustion engines main cause acid rains

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acid rain kills fish and trees

Acid Rain cause a lake become more acidic

Bad effect on ecosystems

Change in pH which organisms are sensitive to. Plants and animals die

Acid rain kill trees. As the acid damages leaves and release toxic substances from soil , making it hard for the trees to take up nutrients

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Greenhouse gases trap energy from the sun

Greenhouse effect - absorb most of the heat  (from sun or earth) that is reflected into space  or reflect heat in all direction .

Not happen - nights on earth very cold

Human beings increase amount of carbon dioxide in atmosphere e.g CO2 increase. Also increase non-greenhouse gas such as NO which enhances effect.

Results in global warming. Results in climate change. Lead to ice caps melting , rise in sea levels. . Effect crop growth . Also cause of habitat loss. 

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Human activity produce lots of greenhouse gases

CO2 - release gas in atmosphere in every day lives e.g car exhausts , burn fossil fuels. 

Deforestation is cutting down of timber , timber being burnt release gas. 

CH4 - Produced naturally e.g rotting plants. 

Can be man-made production e.g rice growing ,cattle rearing . Cows pump out gas

NO - Released naturally by bacteris , soils and ocean . Lot released from soil after fertiliser added

Also released in vehicle engines and industry

CFC - Man-mad chemicals that were once used in aerosol sprays and fridges. Really powerful gases

Most countries don't produce them because they damage ozone layer and prevent UV Radiation reaching earth

CFC still get released from leaked fridges

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Deforestation

Leaching - tress take up nutriens from soil before washed away by rain but nutrients return to soil when leaves and tree die. Trees cut down , nutrients don't get leached away and don't get replaced leaving infertile soils

Balance CO2 and O2 - Forests take up CO2 by photosynthesis and store it in wood and when they decompose , CO2 releases was product of respiration. Trees cut down and burnt - CO2 released at once which distrubs carbon cycle . Contribute global warming. Fewer trees mean less photosynthesis means less O2. Causes O2 levels atmosphere drop

Disturbing Evapotranspiration - Water evaporates from transpiration . water falls back to earth as it rains. Trees cut down , evapotranspiration reduced and climate is drier. 

Soil Erosion - tree roots hold soil together. Trees removed , soil washed away by the rain leaving infertile ground. 

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