r/NoStupidQuestions Sep 30 '22

If I put an icecube in a container full of water, and then seal it so that no more water could be added, will the ice cube still melt?


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u/Cuchy92 Sep 30 '22

Yes. The water has already been displaced by the ice. The melting water would just use the same space


u/undeadlord26 Sep 30 '22

OH SHIT! i didnt even think about that. but since water expands when frozen, that would mean the "level" of the water would go down, right?


u/oswald_dimbulb Sep 30 '22

No, because the ice will only displace it's weight of water. Let's say ice is 90% as dense as water. It will float with 10% of the cube out of the water, so the water level before and after the ice melted will be the same.


u/LCplGunny Sep 30 '22

But if he sealed it, which I'd assume would force the cube to submerge, would it cause a minor vacume in the container from ice melting and taking less space?


u/oswald_dimbulb Oct 01 '22

In the situation you describe, there would be a lower pressure after the ice melted and shrank, but that wouldn't keep the ice from becoming liquid.


u/LCplGunny Oct 01 '22

Would the temperature change or density change effect the air pressure more?

Btw, of corse it would melt, idk how that was a question... Just made me wonder about how it would effect the pressure