How does the density of ice compare to that of liquid water and why is the property important to aquatic organisms?

Question

anonymous · Answer

The density of ice is less than the density of liquid water because when since ice expands, the H20 molecules are being spread out farther apart. This reduces overall density and makes it float on water.

It's important to aquatic organisms because if ice sank under water, then entire oceans/lakes/rivers/ponds/streams/etc. would freeze over eventually instead of just the surface. This would kill anything living in the water. Luckily for us, since ice is less dense than water, it only freezes on the first couple of inches on the surface of these bodies of water so it doesn't kill much of the life under the surface. 

Source: taking AP Bio :)

ookawaiioo · Answer

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