How does volume relate to mass with respect to the water molecule?
This question is not well proposed, because water is volatile.
Vaporize water, and you get a gas, whose volume varies proportionally with temperature.
Because I am too lazy to go thru the calculation, this site reports that the density of water under standard conditions is
We know ice cubes float in a glass of drink; we also know that icebergs float. Of course, this means that the solid state of water is LESS dense than the liquid state. This is a highly unusual property.