Ice is less dense than water. It's important to aquatic organisms because it means that ice floats on water. If this wasn't to happen, aquatic organisms would be frozen in ice deep within bodies of water instead of there being a layer of ice on the waters surface.
Ice is less dense than liquid water due to its lattice structure formed by hydrogen bonds, allowing it to float. This property is vital for aquatic organisms as it creates an insulating layer that protects them from freezing temperatures. Consequently, the water below remains liquid, supporting life during cold conditions.
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