after u drink half of a bottle of water,& recap it,Y does the bottle colapse? What makes it do that?

Question

I like bottled water...and sometimes agter drinking maybe half or so, I bottle it up, and after a couple of hours or a few days, the bittle actually colapses inward. Always wondered what makes it do that. It happens in cold or even hot temperatures. Thanks

Answer 1

Air expands when heated. If you replace the water with warm air and then close the bottle and refrigerate it, the air inside contracts, and the higher air pressure now outside crushes it. If that's the scenario, this is likely the explanation.