C2.4 The Earth

Question 1

What percentage of the Earth’s atmosphere is oxygen?

Answer 1

21%

Question 2

What percentage of the Earth’s atmosphere is nitrogen?

Answer 2

78%

Question 3

Which other gases make up the other 1% of the atmosphere?

Answer 3

Water vapour, carbon dioxide, methane

Question 4

Name the three types of rock

Answer 4

Sedimentary, metamorphic, igneous

Question 5

What are the properties of sedimentary rocks?

Answer 5

They are soft and porous

Question 6

How does freeze thaw occur?

Answer 6

Water gets into the rocks and expands breaking the rock

Question 7

How does chemical weathering occur?

Answer 7

Acid rain reacts with the rocks

Question 8

How does biological weathering occur?

Answer 8

Plant roots grow into the rocks breaking them

Question 9

What is erosion?

Answer 9

Where rocks are broken down into sediment

Question 10

What is transport?

Answer 10

Where water moves sediment to rivers and seas

Question 11

What is deposition?

Answer 11

Where sediment falls to the bottom of sea or river beds

Question 12

What is compaction?

Answer 12

When layers of sediment build up they press down on each other pushing out water

Question 13

How are sedimentary rocks formed?

Answer 13

Rocks are eroded and the sediment is transported to rivers and seas. The sediment is deposited and over many years it is compacted to form sedimentary rocks

Question 14

What are the properties of igneous rocks?

Answer 14

Hard, not porous, made of crystals

Question 15

How are igneous rocks formed?

Answer 15

By cooling lava or magma

Question 16

What are the properties of metamorphic rocks?

Answer 16

Hard, not porous and made of crystals

Question 17

How are metamorphic rocks formed?

Answer 17

By heat and pressure

Question 18

Name 4 ways carbon dioxide is taken out of the atmosphere

Answer 18

• Photosynthesis
• Dissolving in oceans
• Locked up in sedimentary rocks
• Locked up in fossil fuels

Question 19

Name 2 ways carbon dioxide is released into the atmosphere

Answer 19

• Respiration

- Burning fossil fuels

Question 20

How is oxygen put back into the atmosphere?

Answer 20

Photosynthesis

Question 21

Name the three greenhouse gases

Answer 21

Carbon dioxide, methane, water vapour

Question 22

What is global warming?

Answer 22

An increase in the Earth’s average temperature

Question 23

What is climate change?

Answer 23

A long term change in weather