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Sodium salts are present to a greater or lesser degree in all natural waters. Their concentrations vary from a few parts per million in some surface supplies to several hundred grains per gallon in certain good supplies. Sodium is extremely soluble and increases its solubility as the temperature of water rises. Because of this characteristic, sodium salts do not form a scale when water is heated. Likewise, sodium salts do not produce curd when combined with soap. In fact, ordinary soap is an organic sodium compound. As such it does not react with the sodium in water.

Soap may be made from a fatty acid and a strong alkali:

C17H35COOH + NaOH --> C17H35COONa + H20

Stearic acid plus sodium hydroxide reacts to produce sodium stirates plus water

From this, it is evident that soap is actually a salt formed from an acid and a base.

High concentrations of sodium, on the other hand, mean high total minerals and tend to increase the corrosive action of water. In concentrations over 30 to 40 grains per gallon, sodium salts may give water an unpleasant taste. Further, sodium ions in large amounts hamper the operation of ion exchange softeners in the removal of hardness. Where water contains appreciable amounts of both hardness minerals and sodium, several grains of hardness may continue to appear in the softened water. This occurs because of the regenerative action of the sodium ions on the ion exchange material. Sodium salts have a lesser effect on the resinous exchange materials than on those of the gel zeolite type.

Reverse osmosis, distillation, and deionization remove sodium from water.


Wells that contain methane are generally located in areas where gas and oil wells are common sights. Amounts run from 0.1 to 11.6 cubic feet per 1,000 gallons. This is roughly equivalent to 0.8 to 87 milliliters of methane per liter of water. Methane is objectionable in drinking water because of its odor and flammability. When water contains methane gas, it is advisable to aerate it prior to use for either industrial or household purposes. This is necessary to avoid the dangers of fire or explosion. The aerator must be vented to the open air to permit the gas to escape into the atmosphere.


There is a growing trend by both government and private groups to control pollution of water due to the discharge of industrial waste materials. One of the offensive wastes is phenol. Phenol (CsH50H) imparts a medicinal taste and odor to water when the latter is chlorinated. This objectionable taste in chlorinated water occurs in concentrations as low as one part per billion due to the formation of chlorophenols, which may be removed by activated carbon filtration.

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