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Is air an object?
Question Date: 2019-09-26
Answer 1:

This is an interesting question to think about. We usually think of objects as things we can hold and touch and see, but air doesn't quite fit into that description. On the other hand, air is very real: we breathe it all day long, fires couldn't exist without it, and sounds are just the air moving in ways that our ears know how to understand. From this point of view, it would seem that air is quite important.

It might be useful to think about the different states of matter to settle our issue. As you probably know, there are three main ones that we interact with every day: solids, liquids, and gases.

As far as objects go, I think we all tend to think of solids as the most object-y. These are the things we put in our backpacks, make buildings out of, and drive in every day. Solids are things that hold their own shape and don't flow like the other two types of matter. I would definitely consider solids to be objects.

Liquids are things that take the shape of their container, like water in your glass. Even though they change shape, they still stay the same volume. This means that the amount of space your water takes up is the same whether it's in a cup or in your water bottle.

Gases also take the shape of their container, but they fill up the whole volume too! This means that if you put the same amount of gas in a little room or a big room, the gas would fill up both rooms, even though they're made of the same amount of "stuff". The difference is, in the bigger room, the "stuff" would be a lot more spread out. You can tell that gases spread out pretty easily using your nose: When something is cooking in the kitchen, those good-smelling gases don't just stay in the oven, they tend to wander all over the house! (Fun fact: liquids and gases are both part of the same group that scientists call fluids. Even though you might not think of gas as a fluid, it technically is!)

The air you're asking about is a gas, and it might not be an object in the way we usually think about objects. Even so, it's still what birds use to fly, how air conditioners move heat around, and what keeps out the UV rays from the sun, allowing life on Earth to exist! Object or not, air is still pretty cool.

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