Why does ice float on liquid water?
A.
Water in a solid state is less dense than when in a liquid state.
B.
Water in a solid state is more dense than when in a liquid state.
C.
The oxygen atom makes it float.
D.
The hydrogen atom makes it float.

As it cools further and freezes into ice, it actually becomes less dense. ... Ice floats because it is about 9% less dense than liquid water. In other words, ice takes up about 9% more space than water, so a liter of ice weighs less than liter water. The heavier water displaces the lighter ice, so ice floats to the top.

a

explanation:

i believe it is "they are not used up by reactions" as the answer to your question, text me back if this is correct because i just learned this.