Quote:batracio is wrong
Batracio is
RIGHT. That might not be the answer to your riddle, but batracio is right, nevertheless!
I think I know the answer to your riddle. I guess I missed the semantic differences between water and H2O. Water is more than H2O; it is H2O in liquid form.
Anyway, it
IS related to thermal properties of water (and I use water loosely here).
And since your riddle is a mixture of scientific facts and gotchas, one could argue that -- philosophically speaking -- water = 99% H2O (more or less).
Pure H2O is bad for health: try drinking distilled water for a while. Fishes die in pure H2O.
PS: and ice could dilate so much, that it can break the bottle. Every car driver knows that!
So I'm wondering, how "hard" is your bottle?
PPS: this reduces to a problem where the initial conditions matter.
Next.