8I Earth

Question 1

What is the atmosphere?

Answer 1

The mixture of gases around the Earth

Question 2

What percentage of the Earth’s atmosphere is made up of oxygen?

Answer 2

20.90%

Question 3

State 3 processes that involve burning fossil fuels.

Answer 3

Transport, generating electricity, cooking

Question 4

Name 3 fossil fuels.

Answer 4

Coal, oil, natural gas and peat

Question 5

What is the most abundant gas in the atmosphere today?

Answer 5

Nitrogen

Question 6

What is the greenhouse effect?

Answer 6

The trapping of the Sun’s infrared radiation by the Earth’s atmosphere

Question 7

Why isn’t the amount of gases in the atmosphere fixed?

Answer 7

Due to human activities, seasonal changes

Question 8

Name 2 processes that release methane.

Answer 8

Rice production, decomposing landfill waste, water treatment

Question 9

Give 2 examples of decomposers.

Answer 9

Bacteria and fungi

Question 10

Where does carbon enter a food chain?

Answer 10

From carbon dioxide in the air

Question 11

What is the role of decomposers in the carbon cycle?

Answer 11

Break down dead and decaying organisms

Question 12

Name 4 sources of the carbon dioxide in the atmosphere.

Answer 12

Respiration, combustion, decomposition, volcanoes

Question 13

Identify the process that removes carbon from the atmosphere.

Answer 13

Photosynthesis

Question 14

What is a carbon sink?

Answer 14

Stores of carbon

Question 15

Identify an example of a carbon sink.

Answer 15

Fossil fuels, rocks, dissolved in oceans

Question 16

What is the effect of too much carbon dioxide in the atmosphere?

Answer 16

Global warming

Question 17

What is a fossil fuel?

Answer 17

Fuels formed from dead animals or plants that died millions of years ago.

Question 18

Why does driving cause a lot of problems?

Answer 18

Driving involves burning fuel which gives out carbon dioxide.

Question 19

Name two different fuels that can be used in cars.

Answer 19

Petrol or diesel

Question 20

State 2 ways in which humans add to the carbon dioxide levels in the atmosphere.

Answer 20

Burning fossil fuels for transport, generating electricity and power factories.

Question 21

Suggest why fossil fuels are widely used.

Answer 21

They are cheap and easy to use.

Question 22

True or false: increasing plant numbers will increase carbon dioxide levels in the atmosphere.

Answer 22

False.

Question 23

What is meant by vegetation?

Answer 23

Plants

Question 24

What process do plants carry out that uses carbon dioxide?

Answer 24

Photosynthesis

Question 25

What is the natural greenhouse effect?

Answer 25

The natural process of trapping the Sun’s radiation in the air.

Question 26

Name 3 greenhouse gases.

Answer 26

Carbon dioxide, Methane, Water vapour.

Question 27

State 2 impacts of climate change.

Answer 27

Polar ice sheets melting, less water, longer growing seasons, severe weather, more tropical diseases.

Question 28

Suggest how rising sea levels can affect the world.

Answer 28

Flooding leading to Habitat loss.

Question 29

True or false: global warming will cause a reduction in agricultural pests.

Answer 29

FALSE

Question 30

What is the greenhouse effect?

Answer 30

The process of trapping the Sun’s radiation in the air.

Question 31

How much has Earth’s temperature increased in the last century?

Answer 31

0.5°C

Question 32

What is the projected temperature rise over the next 100 years?

Answer 32

1.4 - 5.8°C

Question 33

Name 3 natural resources we cannot survive without.

Answer 33

Biological resources, land, fossil fuels, Metal ores, water.

Question 34

Identify 2 renewable resources.

Answer 34

Solar and Wind

Question 35

Suggest why we need mining.

Answer 35

To extract metal ores from the ground.

Question 36

Why do farmers use pesticides and fertilisers?

Answer 36

To kill pests and provide nutrients for growth

Question 37

True or false: increasing cattle numbers will add to deforestation.

Answer 37

TRUE

Question 38

What is biodiversity?

Answer 38

Variety of different organisms in an area.

Question 39

Identify 2 reasons why huge areas of rainforest are cleared annually.

Answer 39

Farming soya and cattle, mining, building hydroelectric power stations, to sell timber.

Question 40

Explain why local tribespeople are forced off their land.

Answer 40

Their land is useful for the above.

Question 41

Name 3 materials that can be recycled.

Answer 41

Glass, plastic, paper, metals.

Question 42

How much paper does an average family use in a week?

Answer 42

4kg

Question 43

True or false – advantages of recycling are that recycling sites cause pollution.

Answer 43

FALSE

Question 44

Suggest why recycling sites are unsafe and unhygienic.

Answer 44

The recycled materials may not be cleaned.

Question 45

Why are recycling costs often expensive.

Answer 45

Separation of materials requires energy.

Question 46

What is an LCA?

Answer 46

Life cycle analysis.

Question 47

Explain what PET products end up as.

Answer 47

Polyester fibres in clothes or carpets

Question 48

Suggest why people often don’t bother recycling.

Answer 48

There is no economic incentive.

Question 49

What elements are in tin oxide?

Answer 49

Tin and oxygen

Question 50

What can iron ore be mixed with to extract it.

Answer 50

Carbon

Question 51

Give 2 uses each for iron and steel.

Answer 51

Bridges, gates, car bodies, cutlery.

Question 52

Suggest what is formed when carbon reacts with oxygen.

Answer 52

Carbon dioxide

Question 53

True or false: you cannot react some metals with carbon because they’re too reactive.

Answer 53

TRUE

Question 54

Why bother to extract aluminium if it is more expensive to make than iron?

Answer 54

It is lighter than steel and wont rust.

Question 55

Explain why we should recycle aluminium rather than extracting it from its ore.

Answer 55

It is more expensive to extract from its ore.

Question 56

Explain why we shouldn’t dig up more metals.

Answer 56

Mining damages natural habitats and requires more energy than recycling.