Chemistry of the Atmosphere

• What is a life cycle assessment

  we carry our life assessments to asses the environmental impact of a product through all its life

  
• Plastic bags


  • Made from fossil fuels
  • Emit greenhouse gases during production
  • Persist in the environment for centuries
  • Cause pollution and harm to wildlife
• Paper bags


  • Have a smaller environmental footprint than plastic ones
  • Biodegradable
  • Easier to recycle
  • Reduce impact on the atmosphere
• why can you not burn plastic

  as it will give off harmful gasses
• a biodegradable material...


  decomposes naturally over time
• The carbon footprint is the total amount of greenhouse gases emitted over the life cycle of a product, service or event
• A carbon tax is a fee levied on products based on their carbon content.
• Suggest one reason why using solar energy is a more sustainable way of generating electricity than burning oil.

  do not produce air pollution or greenhouse gases when operating
• how the greenhouse effect works

  1. Electromagnetic radiation at most wavelengths passes through the Earth's atmosphere.
  2. The Earth absorbs most of the radiation and warms up.
  3. The Earth radiates energy as infrared radiation.
  4. Some of the infrared radiation goes into space.
  5. Some of the infrared radiation is absorbed by greenhouse gases in the atmosphere.
  6. The lower atmosphere warms up.

  
• name 3 greenhouse gases

  Carbon dioxide, methane and water vapour.
• Human activities are increasing the amount of some greenhouse gases in the atmosphere. For example:

  • farming cattle releases methane
  • farming rice in paddy fields releases methane
  • burning fossil fuels in vehicles and power stations releases carbon dioxide
  • deforestation releases carbon dioxide and reduces the absorption of carbon dioxide through photosynthesis
• what is global warming?

  Global warming is not the same as climate change. Global warming is usually used to describe the warming of the climate in the past 200 years, which the vast majority of scientists are almost certain has been caused by human activities.
• What are the main gases in the Earth’s atmosphere? and what percentage?

  Nitrogen (78%), Oxygen (21%), Argon (0.93%), Carbon Dioxide (0.04%).
• how does the current main gases in the atmosphere compare to gases in the atmosphere 1000 years ago, and what may have caused any changes?

  • Then (1000 years ago):

  • Nitrogen: 78%, Oxygen: 21%, Carbon Dioxide: ~0.03%, Argon: 0.93%.

  • Lower levels of CO2 due to less human activity.

  ---------------------------------------------------------------

  • Now:

  • Nitrogen: 78%, Oxygen: 21%, Carbon Dioxide: ~0.04%, Argon: 0.93%.

  • Increased levels of CO2, due to human activities such as burning fossil fuels, deforestation, and industrial processes.
• How have the oceans influenced the composition of the atmosphere?


  • The oceans absorbed CO2 from the atmosphere, reducing its levels.

  • Photosynthetic organisms in the ocean produced oxygen, which increased the amount of oxygen in the atmosphere over time.

  • Today, oceans still absorb CO2, helping to regulate the atmosphere’s composition.
• what is a products carbon footprint?

  The carbon footprint of a product is the total amount of carbon dioxide (and other greenhouse gases) which are emitted over the full life cycle of a product, service or event.

  For example, the carbon footprint of a car would include the carbon dioxide emitted by:

  • machinery whilst the metal is extracted from the Earth's crust and processed
  • power stations which generate the electricity used to manufacture the car
  • the car itself when it is driven for many years
  • the machinery which is used to dispose of or recycle the car
• What is the formation of acid rain?

  When sulfur dioxide (SO2) and nitrogen oxides (NOx) react with water vapour in the atmosphere, they form sulfuric and nitric acids, which fall as acid rain.
• What are the effects of acid rain?

   Damage to buildings, statues, and plant life, as well as the acidification of rivers and lakes, harming aquatic life.
• What are the consequences of global warming?

  Rising sea levels, more extreme weather (heatwaves, floods), disruption of ecosystems, melting polar ice caps, and damage to crops.
• What is the role of carbon dioxide in global warming?

   Carbon dioxide absorbs infrared radiation and traps heat in the atmosphere, increasing the Earth’s temperature.
• What is the greenhouse effect?

  The process by which greenhouse gases (like CO2, methane) trap heat in the Earth’s atmosphere, preventing it from escaping into space and keeping the Earth warm.
•  How did the Earth’s atmosphere evolve?

  1. Volcanic activity released gases (mainly CO2, water vapour, ammonia, methane).

  2. Water vapour condensed to form oceans.

  3. CO2 absorbed into oceans and used by plants for photosynthesis.

  4. Oxygen levels increased due to photosynthesis by plants, leading to the current atmosphere.
• How is copper extracted from its ore?

  Copper is extracted by smelting the ore and using electrolysis to purify it.
• What is fractional distillation used for in the oil industry?

  Fractional distillation separates crude oil into different fractions based on boiling points for use in fuels, plastics, and chemicals.
• What are the environmental impacts of quarrying for minerals?

  Quarrying can lead to habitat destruction, soil erosion, dust pollution, and disruption of local ecosystems.
• What is the process of hydration of ethene used for?

  The hydration of ethene produces ethanol, which is used in fuel, alcoholic beverages, and industrial solvents.
• Describe how scrap copper wire can be recycled to make new copper water pipes

  wire heated until copper melts then reshaped into pipes
• Suggest why poly(butene) insulation must be removed from scrap copper wire before the copper is recycled.


  any one from:

  • (otherwise) the copper (produced) would be impure

  • (otherwise) the copper (produced) would be a mixture

  • (otherwise) the insulation would burn / melt (during recycling)

  • copper and poly(butene) are recycled by different methods
• Suggest two reasons why recycling scrap copper is more sustainable than extracting copper from copper ore

  (recycling scrap copper)

  • uses less energy

  • conserves copper (ore)

  • (produces) less waste

  • specified environmental impact

  • less landfill required
• Explain why sulfur impurities are removed before petrol is burned in car engines.


  (when burned sulfur impurities) produce sulfur dioxide (which) causes acid rain or (which) causes respiratory problems.
• Explain why the increase in world population may have caused the increase in the concentration of methane in the atmosphere.

  •allow more use of beef cattle (in food production)

  •(which) produces more methane on decomposition
• Describe two potential effects of the increase in the mean temperature of the atmosphere at the Earth’s surface.


  • melting ice

  • rising sea levels

  • flooding

  • extremes of weather

  • loss of habitats
• The mean temperature of the atmosphere at the Earth’s surface has increased.

  Most scientists think that this has been caused by an increase in the concentration of greenhouse gases in the atmosphere.

  Give one reason why some scientists do not accept this theory

  there may be other reasons for changes in the (mean) temperature (of the atmosphere at the Earth's surface)
• Describe what is meant by bioleaching.


  Bioleaching is the process of using bacteria to extract metals from their ores. The bacteria break down the ore, releasing the metal ions into a solution, which can then be collected and processed.
• describe what is meant by Phytomining.

  Phytomining uses plants to absorb metal compounds from the soil. The plants are harvested and burned, and the metal is extracted from the ash.
• Natural gas is a fossil fuel. Describe how deposits of natural gas were formed.

  • Plankton died and sank to the seabed.

  • They were buried by layers of sediment.

  • Over millions of years, high temperature and pressure acted on them.

  • The conditions were anaerobic (without oxygen).

  • This process turned the organic material into natural gas.
• how was crude oil formed?


  Crude oil was formed from the remains of ancient marine plants and animals, buried under layers of sediment millions of years ago. Over time, heat and pressure caused the remains to break down and transform into hydrocarbons, creating crude oil.
• Phytomining has not been widely used to extract copper. why?

  • Slow process: It takes a long time for plants to accumulate enough copper.

  • Low yield: The amount of copper extracted by plants is relatively small compared to traditional mining methods.

  • Cost: It can be more expensive than other methods due to the need for large areas of land and specific conditions.
• What flame colour is produced by copper sulfate solution?


  green