Does water freeze faster when its dense or when its not dense?

No, it gets less dense.As it freezes the hydrogen bonds that make water so cohesive diminish. So as a liquid, water molecules are very close together. When they freeze they are forced into a...

Yes, the density of water decreases as if freezes. Ice float and pipes break as the volume increases with the same mass, which is the definition of density mass per unit volume.

Sycamore wood, sometimes. Sometimes it is denser than water so it sinks. A submarine that is motionless at depth is as dense as the water. A lean person can be as dense as water. Try to think of...

the density of water is 1

because it has a heavy mass but infinite volume