Maintaining Air Quailty Flashcards
Composition of air (%)
Nitrogen - 78%
Oxygen - 21%
Carbon dioxide & other noble gases (mainly argon) - 1%
Common air pollutants
- carbon monoxide
- sulcus dioxide
- oxides of nitrogen (nitrogen monoxide & dioxide)
- methane
- unburnt hydrocarbons
- ozone
Source of carbon monoxide
Incomplete combustion of carbon containing substances
Source of oxides of nitrogen
- internal combustion engines
- lighting activities
Source of sulfur dioxide
- combustion of fossil fuels
- volcanic eruptions
Harmful effects of carbon monoxide
- it permanently binds with haemoglobin in red blood cells and reduces its ability to transport oxygen, thus causing death
How is acid rain formed and its harmful effects
Sulfur dioxide & nitrogen dioxide are acidic oxides and react with oxygen and water to form sulfur if acid and nitric acid respectively (acid rain)
Harmful effects;
- corrosion of metal structures
- corrosion of buildings containing carbonates
- acidification of lakes & rivers, which harm aquatic life
- leaching of nutrients from the soil, which affects the growth of plants
Sulfur dioxide causes irritation of lungs and eyes
How does the carbon cycle regulate the CO2 levels in the atmosphere?
Production:
- when living things respire (glucose -> CO2 + H2O)
- when fossil fuels containing methane are burnt (CO2 + H2O produced)
- when dead organisms are broken down by decomposers (CO2 released)
Removal;
- photosynthesis; when plants convert CO2 & H2O into glucose & O2 in the presence of sunlight & chlorophyll
- CO2 dissolves in Oceans & other water bodies to form carbonate ions, which are converted into calcium carbonate, which makes up the shells of marine organisms and builds up on the seabed when organisms die
- heat waves
- longer & more intense heat waves can cause forest fires and loss of lives. Forest fires destroy ecosystems
Describe the Potential effects of increased levels of greenhouse gases
Climate change
- melting of glaciers and polar ice caps;
- higher average global temperatures causes glaciers and polar ice caps to melt at a faster rate. This results in rising seawater levels, which lead to flooding of low-lying coastal areas.
- ocean currents are disrupted by the addition of large amounts of fresh water due to the melting of polar ice caps, thus worsening climate change
Human activities that increase the production of greenhouse gases
- deforestation, or large-scale clearing for forests, results in an increased amount of carbon dioxide
- combustion of fossil fuels releases CO2 into the atmosphere
- increased breeding of cattle on farms and disposal of waste in landfills lead to an increased amount of methane in the atmosphere