Why does a volume of air shrink as it cools?

Question

I heated about 5-6 oz. of deionized water to about 140-150 degrees F and put it in an empty water bottle and screwed the lid on tight. Over the course of an hour, as it cooled to room temperature, the bottle sucked in quite a considerable amount, like someone took off the cap and squeezed air out and then put the cap back on. Why did this happen?

Answer 1

Hi,

This happened because heated water releases some water vapors. So when you put in hot water and sealed its cap, there is no way air from outside enter it. Now when the vapors cool over a period of time, the convert back to liquid form. As vapors occupy more space than liquid, so when they convert to liquid, there is lesser volume in the bottle than at the time of vapors. So the bottle tries to bulge in as there is no way some other material can come and occupy that space.

hope this helped. keep smiling. bye.

Answer 2

molecules dont move around as much, so they dont hit the walls as much, so the pressure decreases, so the volume decreases.

make it a good day

Answer 3

The volume of air The volume of air becomes denser as it cools.