Water is found to melt and boil at unusually high temperatures; to exhibit unusually large value for surface tension, permittivity (dielectric constant, heat capacity, and heats of phase transition (heats of fusion, vaporization and sublimation); to have a moderately low value attribute of expanding upon solidification; and to posses a viscosity that in light of the foregoing oddities, is surprisingly normal.
In addition, the thermal conductivity of water is large compared to those of other liquids, and the thermal conductivity of ice is moderately large compared to those of other nonmetallic solids.
Of greater is the fact that the thermal conductivity of ice 0 degree C is approximately four times that of water at the same temperature, indicating that ice will conduct heat energy at a much greater rate than will immobilized water.
The thermal diffusivities of water and ice are of even greater interest since these values indicate the rate at which the solid and liquid forms of HOH would undergo changes in temperature.
Ice has a thermal diffusivity approximately nine times greater than that of water indicating that ice, in a given environment, will undergo a temperature change at a much greater rate than will water.
These sizeable differences in thermal conductivity and thermal diffusivity values of water and ice provide a sound basis for explaining why tissues freeze more rapidly than they thaw, when they equal but reversed temperature differentials are employed.
Physical Properties of Water and Ice
