GCSE Chemistry ***NEED TO FINISH***

  1. Petroleum diesel id a fuel made from crude oil . Biodiesel is a fuel made from vegetable oils . To make biodiesel , large areas of land are needed to grow crops from which the vegetable oils are extracted . Large areas of forest are cleared by burning the trees to provide more land for growing these crops
    Image Upload 2use this information and your knowledge and understanding to answer the questions
    Carbon neutral means that there is no increase in the amount of carbon dioxide in the atmosphere
    Suggest why adverts claim that biodiesel is carbon neutral (2)
    • burning biodiesel releases carbon dioxide
    • carbon dioxide is absorbed by the crops
  2. explain why clearing large areas of forest has an environmental impact on the atmosphere (2)
    • increases carbon dioxide
    • because
    • burning trees releases carbon dioxide
  3. suggest why producing biodiesel from crops causes ethical problems (1)
    uses land that could be used for food
  4. suggest why producing biodiesel from crops causes economic problems (1)
    increases the cost of food
  5. about 3000 million years ago , carbon dioxide was one of the main gases in the earths atmosphere
    about 400 million years ago , plants and trees grew on most of the land . When the plants and trees died they were covered by sand and slowly decayed to form coal . Describe and explain how the composition of the earths atmosphere was changed by coal (3)
    • oxygen increased because plants released oxygen
    • carbon dioxide decreased because coal locks up carbon
  6. in some power stations coal is mixed with calcium carbonate . The mixture is crushed before its burned . Explain how the use of calcium carbonate in the mixture increases atmospheric pollution (2)
    calcium carbonate thermally decomposes to produce carbon dioxide
  7. in some power stations coal is mixed with calcium carbonate . The mixture is crushed before its burned . Explain how the use of calcium carbonate in the mixture decreases atmospheric pollution (2)
    sulphur dioxide is removed by reaction with calcium carbonate , this means there is less acid rain
  8. the scientists report claimed that using concrete sleepers instead of wooden sleepers would have less environmental impact . Do you agree with the scientists claim ? Use your knowledge and understanding to justify your answer . Remember to compare using concrete with using wood for the sleepers (4)
    • negative impacts of using concrete rather than wood
    • more fossil fuels needed to produce concrete
    • concrete resources are non-renewable however wood is renewable
    • quarrying limestone destroys habitats whereas growing wood improves habitats
    • making cement releases carbon dioxide whereas wood is carbon neutral
    • positive impacts of using concrete rather than wood
    • less resources are needed as concrete sleepers last longer than wood sleepers
  9. some gold rings aren't made from 100% gold give two reasons why (2)
    • because pure gold has a regular layer of atoms that can slide over each other making pure gold soft
    • gold is a rare metal in the earths crust so it is more expensive
  10. state how nitrogen oxides are produced in a petrol engine
    the nitrogen and oxygen in the air combine because of the high temperatures produced by the engine
  11. many scientists are concerned anout carbon dioxide released from burning fossil fuels such as petrol explain why
    the amount of carbon dioxide in the atmosphere is increasing and carbon dioxide is a greenhouse gas and contributes to global warming
  12. What did Wegner mean by continental drift
    continents were once joined and now the continents are moving apart 
  13. give one environmental and one ethical or social impact of recycling aluminium (2)
    • environmental - less energy is needed to extract aluminium 
    • ethical or social - creates employment 
    •  
  14. to make margerine from olive oil the % of unstaturated fat needs to be decreased give one reason why (1)
    • any one from 
    • * so that it has a higher melting point
    • * so that it is harder  
  15. Limestone is used as a building material . Acid rain dissolves limestone . Limestone contains calcium carbonate . The symbol equation for the reaction of calcium carbonate with hydrochloric acid is shown .
    CaCO3 + 2HCl ===> CaCl+ H2O + CO2
    describe a test to show that carbon dioxide is produced in his reaction (2)
    carbon dioxide is bubbled through limewater , and because  carbon dioxide is present the limewater will turn cloudy 
  16. 200 hundred years ago , scientists thought that the Earth was about 400 million years old . This estimate came from the idea that the centre of the Earth was still molten . More recently , measurements of the of radioactivity in the rocks has shown that the Earths crust is older than 400 million years . 
    Suggest one reason why scientists now know that the Earth is much older than 400 million years (1) 
    radioactivity keeps the core hot
  17. About 50 years ago , new evidence convinced scientists that the Earths crust is made up of tectonic plates that are moving slowly 
    Give two pieces of evidence that have helped to convince these scientists that the tectonic plates are moving (2)
     
    • any two from:
    • • earthquakes
    • • volcanoes
    • • idea of distance between America and Europe / Africa is increasing e.g.continental drift
    • • oceanic ridges
    • • formation of (new) mountain ranges
    • • formation of (new) islands
    • • magnetic stripes
    • •tsunamis
  18. ecess carbon dioixde should be prevented from enetering the atmosphere . Explain why (2)
    • any two from:
    • • it’s a ‘greenhouse gas’ or increase greenhouse effect
    • • causes global warming or increase in the Earth’s temperature
    • • sea-levels rise or flooding
    • • climate change
    • • (polar) ice-caps melt
    • • extension of deserts
  19. Use the digram to explain how carbon dioxide can be prevented from entering the atmosphere (2)
    Image Upload 4  
    • idea trap / store / lock the carbon dioxide
    • in the oil reservoir or under the sea bed
  20. The diagram shows the way in which iron is extracted , used and recycled 

    explain why the recycling of iron is necessary for suistanable development (3)
    • any three from:
    • • conserves / saves resources / metal ores
    • • saves energy resources (used for extraction / processing)
    • • decreases waste materials
    • • decreases a named pollution
  21. the diagram shows the way in which iron is extracted , used and recycled 
    Image Upload 6
     explain why the recycling of iron is neccesary for sustainble development (3)
    • any three from:
    • • conserves / saves resources / metal ores
    • • saves energy resources (used for extraction / processing)
    • • decreases waste materials
    • • decreases a named pollution
    • * accept cheaper / saves money
    • *do not accept acid rain
  22. crude oil is a mixture of mostly alkanes 
    crude oil is sepearted into useful fractions by factional distillation
    describe and explain how the mixture of alkanes is seperated by fractional distillation (3) 
    • heat / evaporate the crude oil / change to gas or vapour cool / condense (hydrocarbons)
    • at different temperatures / boiling points
  23. the C5-C8 fraction has a lowly supply and high in market demand 
    suggest 3 ways in which the oil industry could overcome this problem (3) 
    • any three from:
    • • use different / lighter crude oils
    • • develop markets for low demand fractions
    • • develop new techniques / equipmentto use low demand fractions as fuels
    • • cracking
    • • convert low demand fractions to high demand fractions or bigger molecules to smaller molecules
    • • develop alternative / bio fuels
Author
ghoran
ID
158630
Card Set
GCSE Chemistry ***NEED TO FINISH***
Description
revision
Updated