MOLECULAR STRUCTURE OF WATER
The spheres representing the ions coalesce to some extent, and the molecule might be thought of as a sphere having two rather prominent bubbles of “blisters” attached to it. Te bonds connecting the hydrogen’s to oxygen describe an angle of 105o, so that the two hydrogen are relatively close together on one side of the molecule.
Although this representation of the molecule is somewhat empirical it helps to explain some of the abnormal features of the behaviour of water. The molecule has dipolar properties because the positive charge associated with the hydrogen are connected on one side of the molecule, leaving a degree of negativity on the opposite side. Forces of attraction thus exist between hydrogens of one molecule and the oxygen bonds. They hold molecule together in a fixed pattern in the solid state. In contrast to the orderly arrangement of molecules in crystal of ice, the molecules of liquid water are in a chaotic condition of disorder. Hydrogen bonds still remain an important force but their arrangement is continually shifting
The cohesive forces represented by the hydrogen bonds impact to liquid water is high heat of vaporization. The forces also tend to prevent the passage to electric currents and impart to the fluid its high dielectric constant. The attraction between molecules of a liquid is shown at a liquid surface by the phenomenon called Surface tension. The surface of water is 75.6 dynes per centimeter at 0oC and 71.8 dynes per centimeter at 25oC, which are very high values compared with the many other liquids