This evaporation is one of the principal ways that organisms get rid of excess heat to stabilize their temperatures. The density of water Density is the weight of material per given volume. Usually as the temperature drops, the density of a material increases. This is also true of water until it gets below 4 degrees. Then the molecules move apart to maintain the maximum number of hydrogen bonds, producing an open lattice work configuration.
Ice is less dense than water and thus it floats.
Water is called the universal solvent because the polarity of water is responsible for its capacity to act as a solvent in a solution. Covalently bonded molecules like sugars have regions of partial positive and negative charges. This causes them to have an attraction for water molecules and dissolve in it. Fats lack these polar regions and for this reason are insoluble in water. Water molecules tend to ionize or dissociate into hydrogen ions and hydroxide ions.