Water is a chemical compound composed of a single oxygen atom bonded to two hydrogen atoms (H₂O) which are separated by an angle of 105°. Because of this asymmetrical arrangement, water molecules have a tendency to orient themselves in an electric field, with the positively charged hydrogen toward the negative pole and the negatively charged oxygen toward the positive pole. This tendency results in water having a large dielectric constant, which is responsible for making water an excellent solvent. Water is therefore referred to as the "universal solvent." Since mineral salts and organic materials can dissolve in water, it is the ideal medium for transporting life-sustaining minerals and nutrients into and through animal and plant bodies. Brackish and ocean waters may contain large quantities of sodium chloride as well as many other soluble compounds leached from the crust of the earth. For example, the concentration of mineral...