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Essential Chemistry for IGCSE - Air And Water (Section 2)

1
What does the formula 4Fe + 3O2 + 2xH2O -> 2Fe2O3.xH2O represent?
Answer
(C)
The formation of hydrated iron(III) oxide
2
Which gases are linked to greenhouse effect?
Answer
A
B
3
Which of the following is an example of a natural source of nitrogen oxides?
Answer
(C)
Lightning
4
Which chemical is used to disinfect the water?
Answer
(A)
Chlorine
5
What type of compound is released as a result of the burning of fossil fuels?
Answer
(A)
Hydrocarbons
6
In a diagram of water purification, what is the primary purpose of the settling tank?
Answer
(C)
To allow small particles to settle.
7
Which of the following is/are considered greenhouse gas(es)?
Answer
A
B
D
8
What is the approximate percentage of nitrogen in the air?
Answer
(A)
78%
9
Which statement about the carbon cycle is correct?
Answer
(A)
The carbon cycle keeps the concentration of carbon dioxide in the atmosphere approximately constant.
10
What is the primary source of oxygen separated from the air?
Answer
(B)
Fractional distillation
11
Which of the following is NOT a common air pollutant resulting from burning fossil fuels?
Answer
(D)
Nitrogen.
12
Which substance is essential for washing and cleaning?
Answer
(C)
Water
13
Which of the following is not a significant source of air pollution?
Answer
(D)
Oceans
14
Which of the following is NOT a factor in the rusting process?
Answer
(D)
Carbon Dioxide
15
Which of the following best describes the corrosion of iron and steel?
Answer
(C)
Rusting
16
What causes the greenhouse effect?
Answer
(B)
Greenhouse gases trap heat
17
Which of the following best describes a catalytic converter’s main function?
Answer
(D)
All of the above.
18
What two things are needed for rusting to occur?
Answer
(B)
Water and air
19
Which is a greenhouse gas?
Answer
(C)
Methane
20
Which of the following processes can increase carbon dioxide levels in the atmosphere?
Answer
A
C
D
21
What is the primary purpose of a catalytic converter in a car?
Answer
(B)
To reduce the emission of harmful pollutants.
22
Which of the following is an example of using grease for rust prevention?
Answer
(B)
Lubricating moving parts of machinery
23
What is formed during the incomplete combustion of fuel?
Answer
(B)
Carbon Monoxide
24
What is the purpose of filtration in water treatment?
Answer
(B)
To remove solids
25
What type of reaction is rusting?
Answer
(A)
An oxidation reaction
26
Which statement(s) is/are true about climate change?
Answer
A
B
D
27
What is the purpose of a catalytic converter in a car?
Answer
(A)
To decrease greenhouse gases.
28
Which of the following is NOT a reason for the importance of water?
Answer
(C)
The primary material for construction.
29
What is the main function of a catalytic converter?
Answer
(A)
To remove nitrogen oxides from exhaust gases
30
Which gas is produced during respiration?
Answer
(C)
Carbon dioxide
31
Which of the following is produced by the combustion of fuels?
Answer
(C)
Carbon Dioxide
32
Which of these is not a greenhouse gas?
Answer
(C)
Oxygen
33
Which methods can be used to prevent rust?
Answer
A
B
C
34
Which of the following contributes to climate change?
Answer
A
B
D
35
What is the main gas needed for combustion?
Answer
(B)
Oxygen
36
What is the primary effect of the greenhouse effect?
Answer
(D)
All of the above.
37
Which of the following has been linked to global warming?
Answer
A
C
38
Which is a result of climate change?
Answer
A
B
39
Which of the following is a use of water in a modern city?
Answer
(D)
All of the above
40
How will climate change affect the Earth?
Answer
(C)
Increase in temperature
41
Which of the following is NOT a way to prevent rusting?
Answer
(C)
Exposing to oxygen
42
Which range of wavelengths from the sun is absorbed by the earth?
Answer
(C)
Ultraviolet radiation.
43
Which of the following is a greenhouse gas?
Answer
(C)
Carbon dioxide
44
In water treatment, what process typically follows sedimentation?
Answer
(B)
Filtration
45
What is the process called when small particles clump together and settle at the bottom?
Answer
(B)
Sedimentation
46
What is the approximate percentage of nitrogen in air?
Answer
(B)
78%
47
What is the term for gases that trap heat in the atmosphere?
Answer
(B)
Greenhouse gases
48
What is the primary role of nitrogen in the atmosphere?
Answer
(C)
Diluting the oxygen
49
What step in water purification involves passing water through sand and gravel?
Answer
(A)
Filtration
50
What is a primary component of smog?
Answer
(C)
Sulfur dioxide