My point was that I don't understand where the confusion is as to where the
heat comes from in filling a scuba tank. You are cramming a whole crapload
of molecules into a confined space and it makes heat.

Yes, but you are cramming a whole crapload of =cold= molecules into that
space. The heat generated seems like it wouldn't be enough to
compensate for the cold of the inflowing gas.

That gas is cold because it expanded from the other tank, which was
under even higher pressure.

Jose
--
"Never trust anything that can think for itself, if you can't see where
it keeps its brain." (chapter 10 of book 3 - Harry Potter).
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