# Q & A: does air take up space?

Most recent answer: 05/16/2013
Q:
does air take up space?
- john (age 12)
washington
A:
Hi John-
I'm not sure what that question means. If there's some space around (a box or a room) and there's air in it, the air spreads around in the space. But it leaves lots of room for other things. If you were to squash the air molecules together until they bumped into each other (like they do in cold liquid air) they would occupy only a little fraction of that space.

Mike W.

(published on 10/22/2007)

## Follow-Up #1: Air taking up space

Q:
my question is does air take up space and how would i prove this in an easy experiment...
- lydia (age 8)
A:
Again, I’m not really sure what the question means. But you could blow up a balloon and see that the air you put inside it made it expand. I guess you could say that the air took up space inside the ballooon.

Mike W.

(published on 10/22/2007)

## Follow-Up #2: Air does take up space!

Q:
With regards to does air take up space it does and a simple way to prove it is to use a bicycle pump block the end up with a finger and push it,, you will not be able to push it all the way in because the air is taking up the space until you release your finger hope this helps.
- Anonymous
A:
That's an excellent example!

(published on 10/22/2007)

## Follow-Up #3: Air is there!

Q:
how do you know if air takes up space?? like you can't even see air!! and how come there isn't any air im apce?? where do you get clean air?????? these questions haunt me
- deanndra (age 11)
A:
Most familiar matter exists in three forms, solid, liquid, and gas.   An ice cube, for example is a solid,  it just sits there and doesn't move. You can see it.  Apply some heat and the ice cube melts into water. You can still see it, but as a liquid, it spreads around and sloshes if it is in a glass. If you weigh the ice cube and the amount of water they should be the same.   No matter has vanished.  Now heat the water.  It seems to disappear. It turns into water vapor, a gas.   But if you could collect all the water vapor and weigh it you would find it weighs the same amount.  So nothing has been lost, it just changes form.  The fact that you can't see it just means that your eyes are not sensitive enough. Certain scientific instruments can, though. The water vapor will expand and dissipate  if you don't confine it to a bottle or box, but it does take up space.  For example if you blow up a balloon and squeeze it you can feel that there is something inside it.  That's air. The air that we breathe is made up of several kinds of gasses, mainly Nitrogen.  About 21 percent is Oxygen, the stuff that we can't live without. Several other kinds of gasses are there too.
Why isn't there air in outer space?  It's because the earth's gravity keeps most of it close to home.

LeeH

(published on 05/16/2013)

## Follow-Up #4: Air, matter, and space relationships

Q:
Even though you can't see air it's still there! Because things with matter have mass, and when something has mass it takes up space but it doesn't mean air is taking up all the space. It only takes up a fraction of it. Like a cell, you can only see it under a microscope but it still can take up space.
- Jordan (age 12)
Vermont
A:
Very good point, Jordan.

LeeH

(published on 03/24/2009)