Why does my gas container want to implode?

The gas fumes/air contract with falling temperature more than just air would.

You probably last opened the gas container with fuel when the ambient temperature was relatively warmer than it was when you observed the container collapsing.

Check out this photo:



Since brake fluid absorbs moisture, I thought it would be a good idea to displace the air in the container with the gas from those canned air dusters (the duster air being dry). There was just enough fluid in the container to flush the clutch system and I thought what the heck, I'll just save it until next time. This was during the summer. With the onset of winter and the colder temperatures, the container collapsed.

Basically, you see the same thing happen to gas containers.

I would add that gasoline is a highly volitaile fuild, meaning it vaporizes very easily. kerosine is a heavier fluid that is resonably stable, so when you close the container its normally liquid kerosine and air, when you close the gas container much more of the vapor volume in the container is actually vaporized gasoline then as with kerosine. when it gets cold the gasoline condenses much easier and the amount of air in the container is actually smaller then the equivalent setup with kerosine, so the gas container will crush more. gas being more voliatile in terms of vapor pressures also is why it explodes easier, the fumes catch first, if there not a lot of fumes you can actually extinguish a cigarette in gasoline cause the smoldering temp of the cig is lower then the flash point of liquid gas, however the flash point for gasoline in vapor form is much lower, hence the big boom

Sorry for the long post; I realize I have officially established myself as a dork, but thats what happens when a kid grows up being a pyro and then goes into aerospace engineering

PS If anyone is dumb enough to actually test that cig thing, I refuse to be held responsible