Understanding Air: An Essential Component of Our Environment
Air is a vital element for life on Earth. It is a mixture of gases that surrounds our planet, enabling various processes essential for sustaining life. In this section, we will explore the composition, properties, and significance of air.
Composition of Air
- Air is primarily composed of:
- Nitrogen (78%): The most abundant gas, which helps in plant growth.
- Oxygen (21%): Essential for respiration in humans and animals.
- Carbon Dioxide (0.04%): Crucial for photosynthesis in plants.
- Other Gases: Includes argon, water vapor, and trace gases.
Properties of Air
- Invisible and Odorless: Air cannot be seen or smelled, but it plays a critical role in our environment.
- Compressibility: Air can be compressed, which is why it occupies less space when pressure is applied.
- Temperature Variation: Air temperature can change based on altitude and location, affecting weather patterns.
Significance of Air
- Breathing: Air provides oxygen necessary for all aerobic organisms.
- Weather and Climate: Air plays a crucial role in the formation of weather patterns and climate change.
- Transport of Sound
Conclusion
Understanding air and its properties is essential for recognizing its importance in our daily lives and the environment. It not only sustains life but also influences the climate and weather patterns. By appreciating air, we can better understand the interconnectedness of life on Earth.

Here are some resources for the CBSE Class 7 Social Science chapter "Air" that can help you prepare for a test:

MCQs
Fill in the blanks with the appropriate words to answer questions about the atmosphere, oxygen, carbon dioxide, and more

Important questions
Answer short answer questions like "Define the atmosphere" and "Define air pressure"

NCERT solutions
Find answers to questions like "What is the atmosphere?" and "Which two gases make up the bulk of the atmosphere?"

PDFs
Download free PDFs of important questions and answers to practice and prepare for the exam

The chapter "Air" in the CBSE Class 7 Social Science textbook covers the composition of the atmosphere, its structure, weather, and climate. Air is a mixture of gases that makes up the Earth's atmosphere and is essential for all living beings to survive. The atmosphere is made up of nitrogen, oxygen, water vapor, argon, carbon dioxide, and trace gases.