C10- Questions

Question 1

Describe how the formation of limestone decreased the % of Co2 in the Earth’s atmosphere? (4 marks)

Answer 1

• Co2 from the atmosphere dissolved in the oceans and reacted to form carbonates
• these were used by sea animals/ organisms to form their carbonate containing skeletons and shells
• When the sea animal died, their shells and skeleton fell into the dea bed and became compressed under high pressure and temp
• the co2 was therefore locked up/ trapped in the limeston which reduced Co2 from atmosphere

Question 2

The carbon footprint of concrete production can be reduced by breaking down used concrete and recycling it to make concrete beams. Suggest two reasons why recycling would reduce the carbon footprint of concrete production? (2 marks)

Answer 2

1) Reduce the amount of energy that would be used for recycling than for mining raw materials.
1) Less new concrete would be need to manufactured which would mean fewer CO2 emissions.
1) Less fuel would be needed for the transportation of raw materials

Question 3

Describe actions gov could take to reduce carbon emissions for human activities. Explain why these actions are often limited (4 marks)

Answer 3

Actions

1) CCS technology- invest in research/ technology to capture Co2 before it is released in the atmosphere.
2) Cap on carbon emissions that companies/ indiv allowed to make.
3) Invest in renenwal energy sources or nuclear energy instead of fossil fuel.s
4) Tax companies on the amount of landfill/ waste produced.

Limitations:

• expensive to implement changes.
• concerned about damaging economic growth.
• concerns that without international agreements, the country’s global competitiveness will be harmed if it makes changes but other countries won’t.
• lots of research need to be done on alternative technologies- not sustainable for developing countries and expensive.

Question 4

Suggest how carbon particulates may reduce the extent of global warming? (3 marks)

Answer 4

1) Particulates in the atmosphere cause global dimming.
2) This reduces the amount of energy from the sun that makes it to the Earth’s surface.
3) Less energy that can become trapped in our atmosphere and contribute to global warming

Question 5

Explain the diff in oxygen levels between the Earth’s early atmosphere and Earth’s atmosphere today? ( 3)

Venus has the highest average surface temp of any planet in the solar system, suggest why Venus was so much hotter than Earth today. (5 marks)

Answer 5

1) Venus had a lower % of oxygen as it did not have a photosynthetic plant.
2) Plants and algae evolved over time and began to produce oxygen through photosynthesis
3) Which increased the level of O2 in the Earth’s atmosphere

1) Venus’ atmosphere has a much higher Co2 %.
2) Co2 is a greenhouse gas
3) GG allow the short wavelength radiation to pass through from the Sun and to the planet’s surface
4) But absorb and re-radiate the long wavelength radiation that is reflected back off the surface of the planet.
5) This warms/ insulates the planet which contribuites to the higher average temperature

Question 6

Nitrogen monoxide is a gas formed in vehicle engines. When released, it can combine with oxygen to form Nitrogen dioxide.
Nitrogen dioxide reacts with more water and oxygen in air to form nitric acid.
Give balanced eq for both the formation of nitrogen dioxide from nitrogen monoxide and the formation of nitric acid from nitrogen dioxide. ( 2 marks)

Answer 6

1) 2NO + O2 -> 2NO2

2) 4No2 + 2H20 + O2 -> 4HNO3