The Earth's atmosphere has evolved over the past 4.6 billion years.
Which option correctly shows what has happened to the proportion of each gas during this time period?
| Oxygen | Nitrogen | Carbon dioxide | Water vapour | |
| A | increased | decreased | decreased | decreased |
| B | increased | increased | decreased | decreased |
| C | decreased | increased | increased | increased |
| D | increased | decreased | increased | increased |
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What is the approximate percentage of oxygen in the current atmosphere?
4%
21%
55%
78%
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Green plants undergo photosynthesis.
Which numbers correctly balance the symbol equation for photosynthesis?
__ CO2 + __ H2O → __ C6H12O6 + __ O2
6, 6, 1, 2
6, 12, 2, 6
6, 3, 1, 3
6, 6, 1, 6
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Global climate change has serious consequences on the environment.
Which of the following shows an incorrect effect of global climate change?
| Effect 1 | Effect 2 | |
| A | sea levels rising | storms |
| B | coastal erosion | global dimming |
| C | flooding | ice caps melting |
| D | destruction of habitats | droughts |
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There are many steps involved to produce potable water.
Which of the answers below is the incorrect reason for the treatment being carried out?
| Treatment | Explanation | |
| A | filtration | to remove dissolved solids |
| B | desalination | to remove salt |
| C | reverse osmosis | to remove salt |
| B | sterilisation | to kill bacteria |
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There are certain measures that can be taken to reduce a carbon footprint.
One of these is called carbon capture.
Which statement best describes carbon capture?
Using wind turbines instead of fossil fuels as an energy source
Charging companies or individuals based on the amounts of greenhouse gases they emit
Storing carbon dioxide underground that has been released from burning fossil fuels
Reduce the amount of waste sent to landfill
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Human activities are contributing to the enhanced greenhouse effect.
Which two human activities contribute to the release of methane?
Deforestation and farming
Burning fossil fuels and deforestation
Farming and sending rubbish to landfill
Sending rubbish to landfill and deforestation
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Pollutants released from burning fuels can negatively affect health and the environment.
Which of the following is not the correct effect for the given pollutant?
| Pollutant | Effect | |
| A | carbon dioxide | global warming |
| B | sulfur dioxide | acid rain |
| C | oxides of nitrogen | respiratory problems |
| D | particulates | poisonous |
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Incomplete combustion occurs when there is insufficient oxygen for a reaction.
Which are the two main substances formed during incomplete combustion, aside from water?
Particulates and carbon monoxide
Soot and sulfur dioxide
Carbon dioxide and carbon monoxide
Oxides of nitrogen and sulfur dioxide
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The greenhouse effect allows the Earth to stay warm enough to support life.
Which statement describing the greenhouse effect is true?
Infrared radiation is transferred from the sun to the earth's atmosphere
Infrared radiation emitted by the earth's surface is all absorbed by greenhouse gases
Infrared radiation emitted by the earth's surface is absorbed and re-emitted by greenhouse gases
All wavelengths of radiation are reflected back by the Earth and absorbed by greenhouse gases
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Which type of water is potable water?
Groundwater
Seawater
Tap water
Waste water
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How was the Earth’s early atmosphere formed?
Animals breathing
Global warming
Plants growing
Volcanic activity
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What is the major source of carbon monoxide in the Earth’s atmosphere?
Incomplete combustion of fossil fuels and wood.
Production in a nuclear power station.
The combustion of impurities in coal.
The combustion of impurities in natural gas.
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Look at the following sentences.
They describe one possible theory for how the Earth’s atmosphere evolved.
The sentences are not in the correct order.
What is the correct order for the sentences?
2, 4, 3, 5, 1
2, 5, 4, 3, 1
5, 2, 3, 4, 1
5, 2, 4, 3, 1
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1 markThe table shows the composition of the Earth’s early atmosphere compared with the atmosphere today.
| Nitrogen | Oxygen | Argon | Carbon dioxide | |
| Percentage of gas in the early atmosphere | 4 | 0.5 | 0.5 | 95 |
| Percentage of gas in the atmosphere today | 78 | 21 | 0.9 | 0.04 |
Which gas has changed by the largest percentage from the early atmosphere to the atmosphere today?
Nitrogen
Oxygen
Argon
Carbon dioxide
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Which of these pairs of gases are both greenhouse gases?
Nitrogen and methane
Nitrogen and oxygen
Water vapour and methane
Water vapour and oxygen
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The following statements describe one possible theory for how the Earth’s atmosphere evolved.
The statements are not in the correct order.
What is the correct order for the sentences?
3, 5, 4, 6, 1, 2
3, 6, 5, 4, 1, 2
6, 1, 3, 5, 4, 2
6, 3, 1, 5, 4, 2
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These statements explain how scientists think our modern-day atmosphere was formed.
What is the correct order that these events happened?
1, 4, 2, 5, 3
2, 4, 5, 3, 1
4, 1, 5, 2, 3
4, 2, 5, 1, 3
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Which statement about the greenhouse effect and greenhouse gases is correct?
Greenhouse gases absorb all the infrared radiation that is emitted by the Earth’s surface.
The greenhouse effect is caused by the infrared radiation being absorbed and re-emitted by greenhouse gases.
The lower the concentration of greenhouse gases in the Earth’s atmosphere, the warmer the Earth becomes.
Greenhouse gases are a large percentage of the Earth’s current atmosphere.
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