Introduction and Composition of atmosphere

1. What are the four natural systems of Earth?
A) Hydrosphere, Lithosphere, Biosphere, Atmosphere
B) Atmosphere, Stratosphere, Troposphere, Exosphere
C) Lithosphere, Atmosphere, Thermosphere, Exosphere
D) Atmosphere, Hydrosphere, Troposphere, Exosphere

2. Which of the following is not one of Earth’s natural systems?
A) Lithosphere
B) Hydrosphere
C) Stratosphere
D) Atmosphere

3. The study of which natural system is the focus of this chapter?
A) Hydrosphere
B) Atmosphere
C) Lithosphere
D) Biosphere

4. What is the atmosphere?
A) A layer of water surrounding Earth
B) The envelope of gases surrounding Earth
C) The rocky surface of Earth
D) The layer beneath Earth’s surface

5. What percentage of the atmospheric mass lies within the lowest 11 kilometers of the surface?
A) 25%
B) 50%
C) 75%
D) 99%

6. Which gas has the highest percentage in the composition of dry air?
A) Oxygen
B) Carbon dioxide
C) Argon
D) Nitrogen

7. What is the percentage of nitrogen in the atmosphere by volume?
A) 50.00%
B) 78.09%
C) 20.94%
D) 0.93%

8. Which gas makes up 20.94% of the atmosphere?
A) Nitrogen
B) Oxygen
C) Argon
D) Carbon dioxide

9. What is the approximate percentage of carbon dioxide in the atmosphere?
A) 0.93%
B) 0.03%
C) 20.94%
D) 78.09%

10. Which of the following gases constitutes about 0.93% of the atmosphere?
A) Nitrogen
B) Argon
C) Oxygen
D) Carbon dioxide

11. Which atmospheric layer lies closest to Earth’s surface?
A) Stratosphere
B) Troposphere
C) Mesosphere
D) Exosphere

12. What percentage of sunlight is reflected back into space due to clouds, gases, and dust particles?
A) 6%
B) 26%
C) 32%
D) 18%

13. How much sunlight is absorbed by atmospheric gases?
A) 18%
B) 26%
C) 32%
D) 50%

14. What percentage of sunlight reaches Earth’s surface and is absorbed by it?
A) 18%
B) 26%
C) 50%
D) 32%

15. What type of energy is absorbed by Earth’s surface and then transformed into heat energy?
A) Solar energy of short wavelength
B) Solar energy of long wavelength
C) Electrical energy
D) Magnetic energy

16. What is the wavelength of the radiated heat energy absorbed by water vapors and CO2 in the atmosphere?
A) Short
B) Long
C) Medium
D) Infinite

17. What gas in the atmosphere absorbs the long-wavelength heat energy radiated by Earth?
A) Nitrogen
B) Oxygen
C) Carbon dioxide
D) Argon

18. Which layer of the atmosphere contains 75% of the atmospheric mass?
A) Stratosphere
B) Troposphere
C) Mesosphere
D) Exosphere

19. Which component of the atmosphere reflects 6% of sunlight back into space?
A) Earth’s surface
B) Clouds
C) Dust particles
D) Gases

20. Which gas is responsible for 78% of Earth’s atmosphere?
A) Oxygen
B) Nitrogen
C) Carbon dioxide
D) Argon

21. Which process converts solar energy absorbed by Earth’s surface into heat energy?
A) Reflection
B) Radiation
C) Absorption
D) Photosynthesis

22. What percentage of sunlight is reflected by Earth’s surface?
A) 18%
B) 6%
C) 50%
D) 26%

23. Which atmospheric gas has the smallest percentage by volume?
A) Nitrogen
B) Oxygen
C) Carbon dioxide
D) Argon

24. Which two gases primarily absorb heat energy radiated by Earth’s surface?
A) Nitrogen and oxygen
B) Water vapor and CO2
C) Argon and oxygen
D) Nitrogen and CO2

25. Which atmospheric layer is responsible for absorbing the majority of harmful ultraviolet (UV) radiation?
A) Troposphere
B) Stratosphere
C) Mesosphere
D) Exosphere

26. What role do water vapors and carbon dioxide play in Earth’s atmosphere?
A) They absorb short-wavelength radiations.
B) They absorb long-wavelength heat energy radiated from Earth.
C) They reflect sunlight directly.
D) They produce nitrogen gas.

27. How does human activity affect the atmosphere?
A) It stabilizes the atmosphere.
B) It causes no changes.
C) It gradually disturbs the natural systems.
D) It decreases pollution levels.

28. What term describes the envelope of gases surrounding the Earth?
A) Lithosphere
B) Hydrosphere
C) Atmosphere
D) Biosphere

29. Which of the following is a source of global warming?
A) Reduced levels of carbon dioxide
B) The release of ozone into the atmosphere
C) Excessive emission of greenhouse gases like CO2
D) Increased levels of nitrogen

30. Which gas in the atmosphere helps in regulating Earth’s temperature by trapping heat?
A) Nitrogen
B) Oxygen
C) Argon
D) Carbon dioxide

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Correct Answers:

1. A
2. C
3. B
4. B
5. C
6. D
7. B
8. B
9. B
10. B
11. B
12. B
13. A
14. C
15. A
16. B
17. C
18. B
19. A
20. B
21. B
22. B
23. C
24. B
25. B
26. B
27. C
28. C
29. C
30. D