| Date | May 2019 | Marks available | 2 | Reference code | 19M.3.hl.TZ2.18 |
| Level | HL | Paper | 3 | Time zone | TZ2 |
| Command term | Describe | Question number | 18 | Adapted from | N/A |
Question
This question is about global warming.
Describe the effect of infrared (IR) radiation on carbon dioxide molecules.
Outline one approach to controlling industrial emissions of carbon dioxide.
Markscheme
bond length/C=O distance changes
OR
«asymmetric» stretching «of bonds»
OR
bond angle/OCO changes [✔]
polarity/dipole «moment» changes
OR
dipole «moment» created «when molecule absorbs IR» [✔]
Note: Accept appropriate diagrams.
Any one of:
capture where produced «and store» [✔]
use scrubbers to remove [✔]
use as feedstock for synthesising other chemicals [✔]
carbon credit/tax/economic incentive/fines/country specific action [✔]
use alternative energy
OR
stop/reduce use of fossil fuels for producing energy [✔]
use carbon reduced fuels «such as methane» [✔]
increase efficiency and reduce energy use [✔]
Note: Do not accept “planting more trees”.
Accept specific correct examples.
Examiners report
This part was fairly well answered with most candidates receiving one of the two marks. There were many candidates who stated asymmetric stretching and bonds vibrate but missed writing polarity and dipole changes, which deprived them of the second mark.
This part was reasonably answered although there were many candidates who gave vague answers that did not receive marks.
Syllabus sections
- 17N.3.sl.TZ0.13d: Outline how water and carbon dioxide absorb infrared radiation.
-
18M.3.sl.TZ1.9a:
Identify one naturally occurring greenhouse gas, other than carbon dioxide or water vapour, and its natural source.
-
19M.3.hl.TZ1.15d(ii):
Compare methane’s atmospheric abundance and greenhouse effect to that of carbon dioxide.
-
17M.3.sl.TZ1.17d:
Many combustion processes also release particulate matter into the atmosphere. Suggest, giving your reason, how this might affect the temperature of the Earth’s surface.
-
18M.3.sl.TZ1.9c:
The concentrations of oxygen and nitrogen in the atmosphere are much greater than those of greenhouse gases. Outline why these gases do not absorb infrared radiation.
- 18N.3.hl.TZ0.14c: Contrast the importance of carbon dioxide and methane as greenhouse gases.
- 18N.3.sl.TZ0.11d: Contrast the importance of carbon dioxide and methane as greenhouse gases.
-
17M.3.sl.TZ1.17c:
Outline, giving the appropriate equation(s), how increasing levels of carbon dioxide will affect the pH of the oceans.
-
17M.3.sl.TZ2.14a:
Identify which region, A or B, corresponds to each type of radiation by completing the table.
-
19M.3.sl.TZ2.13a:
State one greenhouse gas, other than carbon dioxide.
-
17M.3.sl.TZ1.17a:
Suggest why it is only in recent years that specific predictions of the future effects of fossil fuel combustion have been made.
-
19M.3.sl.TZ1.11d(ii):
Compare methane’s atmospheric abundance and greenhouse effect to that of carbon dioxide.
-
16N.3.sl.TZ0.13b:
(i) Describe the changes that occur at the molecular level when atmospheric carbon dioxide gas absorbs infrared radiation emitted from the Earth’s surface.
(ii) Other than changes to the acidity of oceans, suggest why the production of carbon dioxide is of greater concern than the production of water vapour.
-
20N.3.hl.TZ0.11e(ii):
Methane is another greenhouse gas. Contrast the reasons why methane and carbon dioxide are considered significant greenhouse gases.
-
18M.3.sl.TZ2.11a:
Explain the molecular mechanism by which carbon dioxide acts as a greenhouse gas.
-
19M.3.sl.TZ1.11d(i):
Explain how methane absorbs infrared (IR) radiation by referring to its molecular geometry and dipole moment.
-
18M.3.sl.TZ2.11b:
Discuss the significance of two greenhouse gases, other than carbon dioxide, in causing global warming or climate change.
-
19M.3.hl.TZ1.15d(i):
Explain how methane absorbs infrared (IR) radiation by referring to its molecular geometry and dipole moment.
-
17N.3.sl.TZ0.13c:
Climate change or global warming is a consequence of increased levels of carbon dioxide in the atmosphere. Explain how the greenhouse effect warms the surface of the earth.
-
18N.3.sl.TZ0.11e:
Explain, using an equation, the effect of increased carbon dioxide in the atmosphere on the pH of lake water.
-
16N.3.sl.TZ0.13a:
Explain the effect of the increasing concentration of atmospheric carbon dioxide on the acidity of oceans.
-
18N.3.hl.TZ0.14d:
Explain, using an equation, the effect of increased carbon dioxide in the atmosphere on the pH of lake water.
-
19M.3.hl.TZ2.18b:
Outline one approach to controlling industrial emissions of carbon dioxide.
-
17M.3.sl.TZ2.14b.ii:
Describe how large amounts of CO2 could reduce the pH of the ocean using an equation to support your answer.
-
19M.3.sl.TZ2.13c:
Outline one approach to controlling industrial emissions of carbon dioxide.
-
20N.3.hl.TZ0.11e(i):
When combusted, all three fuels can release carbon dioxide, a greenhouse gas, as well as particulates. Contrast how carbon dioxide and particulates interact with sunlight.
-
19M.3.sl.TZ2.13b:
Describe the effect of infrared (IR) radiation on carbon dioxide molecules.
-
20N.3.sl.TZ0.9f(i):
When combusted, all three fuels can release carbon dioxide, a greenhouse gas, as well as particulates. Contrast how carbon dioxide and particulates interact with sunlight.
-
17M.3.sl.TZ1.17b:
Carbon dioxide has two different bond stretching modes illustrated below.
Predict, with an explanation, whether these stretching modes will absorb infrared radiation.
-
18M.3.sl.TZ1.9b:
Formulate an equation that shows how aqueous carbon dioxide produces hydrogen ions, H+(aq).
-
17M.3.sl.TZ2.14b.i:
Oceans can act as a carbon sink, removing some CO2(g) from the atmosphere.
CO2(g) CO2(aq)
Aqueous carbon dioxide, CO2(aq), quickly reacts with ocean water in a new equilibrium reaction. Construct the equilibrium equation for this reaction including state symbols.
-
20N.3.sl.TZ0.9f(ii):
Methane is another greenhouse gas. Contrast the reasons why methane and carbon dioxide are considered significant greenhouse gases.
