CHAPTER 13

Question 1

How do scientists collect data on what earth was like 2

Answer 1

gas bubbles trapped in rocks

data gathered from other planets and their moons

Question 2

what was the first phase in the evolution of the atmosphere

Answer 2

the surface was covered in volcanoes which released co2 and oxygen
then nitrogen water vapour and methane and ammonia were released by volcanoes

Question 3

what gases would the early atmosphere be made from

Answer 3

mostly carbon dioxide and a little oxygen

Question 4

how were oceans formed

Answer 4

water vapour in the atmosphere condensed as the planet cooled
icy comets melted and released water

Question 5

what happened to the co2 in the atmosphere once oceans were formed

Answer 5

it dissolved into the water and formed carbon precipitates that formed sediments on the sea floor

Question 6

what happened once algae had evolved

Answer 6

they absorbed the co2 from the oceans to photosynthesis and produce o2 as a waste product

Question 7

how are sedimentary rocks formed

Answer 7

when organisms die they sink to the sea bed and are covered in layers of sediment
they then become compressed and form rocks with clear layers

Question 8

what is coal made from

Answer 8

compressed plant deposits

Question 9

what is crude oil made from

Answer 9

compressed plankton

Question 10

what is limestone made from

Answer 10

calcium carbonate

Question 11

what happened once more plants evolved to photosynthesis

Answer 11

they absorbed much of the co2 and released more o2 into the atmosphere more complex animals could now evolve

Question 12

overall process of the evolving atmosphere

Answer 12

volcanoes produced gases like co2 and nitrogen oceans were formed
green plants started to photosynthesis co2 was removed and o2 released more complex animals could survive

Question 13

what happens when animals eat plants

Answer 13

the co2 in the plant is transferred to the animals tissues

Question 14

how was coal formed

Answer 14

plant material deposited into swaps they were bused in aerobic conditions and compressed for millions of years

Question 15

how was limestone formed

Answer 15

animals ingested co2 through plants they die build up of skeletons on seabeds
pressure of other sediments forms this sedimentary rocks

Question 16

how were crude oil and natural gases formed

Answer 16

remains of plankton were deposited into the mud on the sea bed these were covered in sediments they were compressed gas and oil are found in this rocks

Question 17

what are the main 2 ways in which co2 was removed from the atmosphere

Answer 17

photosynthesising in to plants dissolving in oceans

Question 18

how was methane and ammonia removed from the atmosphere

Answer 18

they reacted with o2

Question 19

equation for ammonia + o2

Answer 19

ammonia + o2 -> nitrogen and water

Question 20

equation for methane + o2

Answer 20

methane + o2 -> carbon dioxide + water

Question 21

what are the main 4 gases in the current atmosphere

Answer 21

nitrogen
oxygen
argon
co2

Question 22

percentage of nitrogen in atmosphere

Answer 22

78

Question 23

percentage of o2 in atmosphere

Answer 23

21

Question 24

percentage of argon in atmosphere

Answer 24

0.9

Question 25

percentage of co2 in atmosphere

Answer 25

0.04

Question 26

evidence against global warming

Answer 26

natural flutactions in earth temperature

Question 27

one way of measuring the link between co2 levels and climate

Answer 27

ice cores are drilled from glaciers which have co2 gases inside

Question 28

how does deforestation impact on co2 levels

Answer 28

carbon sinks like rainforests are cut down

less co2 is removed from air by these trees co2 is also released

Question 29

how do rising oceans temperatures affect co2 levels

Answer 29

co2 is less soluble in warm water

oceans less effective

Question 30

what are methane levels rising 2

Answer 30

increased cattle farming

landfill sites = more methane released by decomposition

Question 31

what is the greenhouse effect

Answer 31

sun emits short length radiation this passes through the greenhouse gases in the atmosphere
the earth heats up it emits infrared radiation to cool down this is absorbed by the gases
re radiated towards earth and heats it up