AMP

Chapter 7: Composition and Structure of Atmosphere — Online MCQ Test

GEOGRAPHY · Grade 11 · CBSE(NCERT)
Practice Chapter 7: Composition and Structure of Atmosphere with a free chapter-wise online MCQ test. This chapter covers: Atmosphere troposphere stratosphere mesosphere thermosphere atmospheric gases ozone weather climate atmospheric layers. AI-generated questions from basic to board-exam level, with instant results and explanations.

Start Exam on Full Site →

Chapter 7: Composition and Structure of Atmosphere — Important Questions & Answers

Which gas forms the largest part of the Earth's atmosphere by volume?
  • A. Oxygen
  • B. Nitrogen
  • C. Carbon dioxide
  • D. Argon
Answer: B. Nitrogen
Nitrogen is the most abundant atmospheric gas, making up about 78% of the air by volume.
The layer of the atmosphere in which weather phenomena occur is called:
  • A. Stratosphere
  • B. Mesosphere
  • C. Troposphere
  • D. Thermosphere
Answer: C. Troposphere
All major weather changes such as clouds, rainfall, and storms occur in the troposphere.
The temperature in the troposphere generally decreases with increase in altitude because:
  • A. The layer is heated mainly from below by the Earth's surface
  • B. It contains no water vapour
  • C. Oxygen becomes heavier at higher levels
  • D. Solar radiation cannot enter the troposphere
Answer: A. The layer is heated mainly from below by the Earth's surface
The troposphere receives heat from the Earth's surface, so temperature falls as one goes upward.
A plane is flying at a height where the air is stable and free from most weather disturbances. In which layer is it most likely flying?
  • A. Troposphere
  • B. Stratosphere
  • C. Mesosphere
  • D. Thermosphere
Answer: B. Stratosphere
The stratosphere is relatively calm and stable, so aircraft often fly in its lower part to avoid weather disturbances.
Consider the following statements: 1. The atmosphere is composed mainly of nitrogen and oxygen. 2. Water vapour and dust are permanent gases. 3. Carbon dioxide is important for photosynthesis and heat retention. Which of the statements given above is/are correct?
  • A. 1 only
  • B. 1 and 3 only
  • C. 2 and 3 only
  • D. 1, 2 and 3
Answer: B. 1 and 3 only
Nitrogen and oxygen are the major gases, and carbon dioxide is important for photosynthesis and warming. Water vapour and dust are variable, not permanent, components.