Air

Key Notes:

What is Air?

• Air is a mixture of gases that surrounds the Earth.
• It is invisible but we can feel it when it moves (wind).

Composition of Air:

• Air contains several gases, the most important being oxygen, nitrogen, and carbon dioxide.
• Oxygen helps us breathe, while nitrogen is the most abundant gas in the air.

Importance of Air:

• Air is essential for life. Plants, animals, and humans need oxygen to survive.
• Plants also need carbon dioxide in the air for photosynthesis (making their food).

Properties of Air:

• Air has weight, although it is not easy to see or feel it.
• Air can move, creating wind, which helps carry pollen, seeds, and water vapor.
• Air can be warm or cold, and it can contain moisture (humidity).

Uses of Air:

• Air helps in the movement of wind, which is important for weather patterns.
• We use air for breathing, flying (airplanes), and even in tools like windmills.

Air Pollution:

• Sometimes air becomes polluted due to smoke, dust, and harmful gases from factories and cars.
• It is important to keep the air clean by reducing pollution.

Experiment:

• Simple activities like blowing up a balloon show that air occupies space and has volume.

Conclusion:

• Air is all around us, and without it, living things cannot survive. It is important to take care of our air to keep the Earth healthy.