Justify air is matter and prove air is present all around us
Have you ever wondered if the air around you is made of something? Well, the answer might surprise you! Even though we can't see it, touch it, or hold it in our hands, air is indeed a type of matter. In this exploration, we'll uncover the hidden secrets of air, discover what it's made of, and learn why understanding air as matter is so important. So, let's embark on a journey to unravel the mysteries of the seemingly invisible substance that surrounds us every day!
Imagine air like a big group of tiny, invisible particles floating around us. Even though we can't see them, these particles have a few special qualities that make air a kind of matter.
Matter means anything that has mass and volume (takes up space). Air has mass because it's made up of lots of these tiny particles. And when these particles get together, they fill up space – just like when you blow up a balloon, you're filling it with air.
The closer we are to Earth, the more air is pressing down on us because there are more air particles above. This is why air pressure is higher at sea level and lower at higher elevations, like the top of a mountain.
1. Air Occupies Space:
We can confirm that air occupies space because when air is blown, it fills the empty area. The more air you blow, the more it will expand, proving that air occupies space2.
Fig. 2.1 Air occupies space
Watch this experiment here:
Vid. 2.1 Air occupies space4
Applications: Cycle tires, balloons, and balls are filled with air because air is a gas that takes up space and can be compressed. When you pump air into these objects, the particles of air spread out and fill the entire space inside. The compressed air pushes against the inside walls, making the tire, balloon, or ball firm and able to hold its shape. This is why a tire stays inflated and supports the weight of a bicycle, and why a balloon or ball becomes round and bouncy when filled with air.
2. Air has mass
Although we cannot see air, we can feel its presence.
Are you wondering if air has weight?
In this scientific experiment, the "Balloon Balance Experiment," we can satisfy your curiosity about "air weight".
Let's begin5!
Vid. 2.2 Air has weight5
Air is a real substance(matter), it has mass and therefore weight.
3. Air exerts pressure
Air not only has mass, but it also exerts pressure. The particles in the air push in all directions, and this force is known as air pressure.11
The books at the bottom feel the most weight because they have all the books above them pressing down. Similarly, the air near the Earth's surface feels the weight of all the air above it, so it is squeezed closer together. This squeezing creates higher air pressure.
Now, think about being on a tall mountain. There isn’t as much air above you pressing down because you're higher up. This is why there is less air pressure at the top of a mountain compared to at sea level.
So, closer to the Earth = more weight of air above = more air pressure. Higher up = less weight of air above = less air pressure!
Fig. 2.3 Air Pressure is lower on mountains and higher on the surface of earth
Let’s watch this video12 to see a demonstration to prove air exerts pressure:
Vid. 2.3 Air exerts pressure
There is air all around us and across the entire planet. It surrounds us in every direction. Although we cannot see the air, as it moves, we can sense its presence.
Moving air is called wind.
Gently blowing air is a breeze.
There is a layer of air encircling our planet. The term "atmosphere" refers to this layer, which rises many kilometres above the surface of the earth. The air becomes more scarce as we move higher in the skies6.
Fig. 2.5 Earth's Atmosphere
Examples to prove air is everywhere2:
Let us use the Claim- Evidence- Reasoning structure to explain with evidence that air is everywhere.
Vid 2.3 Wind uprooting a tree8
Let us watch this video and try the activity in the read aloud9!
Vid 2.4 Air is Omnipresent
Glossary
matter: anything that takes up space and can be weighed
mass: measure of the quantity of matter in an object
volume: the amount of space that something contains or fills
atmosphere: a mixture of gases that surrounds the Earth
scarce: not existing in large quantities; hard to find
Summary
Air is matter.
Matter means anything that has mass and volume (takes up space).
Air has mass because it's made up of lots of these tiny particles that occupy space.
Air exerts pressure.
We can’t see or touch air but we can feel it and observe its effects. e.g; we can feel the air when it moves, we can observe when a windmill or any object moves due to air.
References
1 Air is Matter, MnSTEP,(n.d) link
2 7 Properties of Air. Denwool, 2020, ,link
3 Galaxy A Course in Science Book 6>Air>Put on your thinking cap>Q 7, Embibe,(n.d) link
4 Does air occupy space? Experiment 5 , Youtube, Kaathadi, (n.d) link
5 Air has Weight (Learn by doing). Youtube, MITR Books,(n.d) link
6 Presence of Air Around Us: Composition, Importance. Embibe, 2023,link
7 Air Around us. Practically, (n.d) link
8 Caught on camera: Strong winds uproot giant tree in New Zealand. Euronews, Youtube, (n.d) link
9 Air is All Around You - (Read Aloud). Youtube, STEMHAX,(n.d) , link
10 Air is stuff. How things fly, n.d, link
11 Air. Science World, n.d, link
12 Air has weight and exerts pressure. Youtube,n.d, link