C1.2a How oceans remove carbon dioxide Name
Class
Date
Cut out the cards below and rearrange them to show how most carbon dioxide was removed from Earth’s early atmosphere. Use arrows between the boxes. There should be one starting point, but three finishing points. You will need to use some cards more than once.
Compounds used to create shells of marine organisms
Sediments become sedimentary rock
Sediments become sedimentary rock
Marine organisms die and fall to the sea floor
Plants and algae die and decay to form fossil fuels
Carbon dioxide dissolves in the oceans
Some carbon dioxide remains dissolved as carbon dioxide
Algae and plants in the sea absorb carbon dioxide for photosynthesis
Carbon dioxide in the atmosphere
Marine organisms decay, but shells remain in sediment
Š Pearson Education 2010. Edexcel GCSE Science Activity Pack. This document may have been altered from the original.
C1.2b The changing atmosphere Name
Class
Date
The data below shows how the amounts of carbon dioxide, oxygen and nitrogen may have changed during the Earth’s history. Age of Earth (billions of years)
Carbon dioxide (%)
Oxygen (%)
Nitrogen (%)
0
90
0
10
0.5
40
0
25
1.0
21
0.5
40
1.5
15
1
50
2.0
10
5
60
2.5
7
10
70
3.0
5
18
75
3.5
2
20
78
4.0
1
21
78
4.6 (today)
0.038
21
78
1
Draw a line graph using this data. Plot the age of the Earth on the horizontal axis and the percentage of each gas on the vertical axis. Draw a line of best fit for each gas and label these lines clearly.
2
Label any significant places on your graph where the amount of the gases starts to change significantly. Explain why they change in each case where possible. _________________________________________________________________ __________________________________________________________________ __________________________________________________________________
Š Pearson Education 2010. Edexcel GCSE Science Activity Pack. This document may have been altered from the original.
C1.2c Removing carbon dioxide from the atmosphere
1
2
Much of the carbon dioxide in the early atmosphere is thought to have been removed once oceans formed. a
Give one way in which processes in the oceans could have removed carbon dioxide from the air.
b
Describe how the carbon dioxide could have become locked up in carbonate rocks.
c
Suggest why the amount of carbon dioxide in the air did not start to fall until the oceans formed and life evolved.
Carbon dioxide dissolves in water. 1.69 grams of carbon dioxide dissolves in 1 dm3 of water at 20 °C. (1 dm3 equals 1000 cm3 or 1 litre; 1 m3 = 1000 dm3) Calculate the mass of carbon dioxide that dissolves in each of cases a–c. Assume that the water is at 20 °C.
3
a
In a garden pond measuring 250 cm long, 80 cm deep and 150 cm wide.
b
In Kielder reservoir in Northumberland, which holds about 200 000 000 000 dm3 – that’s 2 × 1011 dm3 – of water.
c
In all the world’s oceans, which are estimated to contain about 1.3 billion km3 of water (1.3 x 1018 m3).
Over the history of the Earth, the oceans have dissolved more than the mass of carbon dioxide calculated in question 2c. Suggest why.
Extra challenge 4
Find out how a change in global temperatures would affect the amount of carbon dioxide dissolved in the oceans, and so the amount in the atmosphere.
© Pearson Education 2010. Edexcel GCSE Science Activity Pack. This document may have been altered from the original.
C1.2d Are water vapour and carbon dioxide present in the air? Name
Class
Date
Air is a mixture of gases. In this experiment you are going to test to prove that air contains water vapour and carbon dioxide. To test for water vapour you will use cobalt chloride paper which turns pink in the presence of water. To test for carbon dioxide you will use hydrogencarbonate indicator which turns from purple to orange/red in the presence of carbon dioxide.
Apparatus
Health and safety
boiling tube
●
Wear eye protection
boiling tube bung with delivery tubes and one-way valves
●
Cobalt chloride is toxic. Handle as little as possible, using forceps, and wash your hands after the experiment.
●
When placing the bung in the boiling tube, hold the bung (not the delivery tubes) and the boiling tube near the neck.
boiling-tube rack hydrogencarbonate indicator dry cobalt chloride paper plastic syringe forceps Testing for water vapour
A Collect a piece of dry cobalt chloride paper, which should be blue, and leave it on the bench in the air for a few minutes. Look for any colour change. Testing for carbon dioxide B Place some hydrogencarbonate indicator solution in a boiling tube to about one third depth in a boiling-tube rack. C Carefully place the bung with the delivery tubes in the boiling tube. Hold the bung (not the delivery tubes) and the boiling tube near the neck. The tubes with one-way valves are attached to the short delivery tube that does not go into the indicator.
one way valves
syringe
D Attach the syringe to the delivery tube with the valves. E Pull the syringe plunger to pull air through the solution. Then empty the air out of the syringe by pushing the barrel back in. The air will escape through the one way valve and not pass into the solution. Repeat this several times.
Recording your results 1
Describe the results you got for each test
Considering your results/conclusions 2
Explain what your results tell you about air.
© Pearson Education 2010. Edexcel GCSE Science Activity Pack This document may have been altered from the original.
delivery tubes boiling tube in rack water and hydrogencarbonate indicator