Water is the common name applied to the liquid form (state) of the hydrogen and oxygen compound H2O. Pure water is an odorless, tasteless, clear liquid. Water is one of nature's most important gifts to mankind. Essential to life, a person's survival depends on drinking water. Water is one of the most essential elements to good health -- it is necessary for the digestion and absorbtion of food; helps maintain proper muscle tone; supplies oxygen and nutrients to the cells; rids the body of wastes; and serves as a natural air conditioning system. Health officials emphasize the importance of drinking at least eight glasses of clean water each and every day to maintain good health.
Since water contains no calories and can serve as an appetite suppressant and helps the body metabolize stored fat, it may possibly be one of the most significant factors in losing weight. In his book, titled "The Snowbird Diet" Dr. Donald Robertson says the body will not function properly without enough water and discusses the importance of drinking plenty of water for permanent weight loss: "Drinking enough water is the best treatment for fluid retention; the overweight person needs more water than the thin one; water helps to maintain proper muscle tone; water can help relieve constipation; drinking water is essential to weight loss."
Water is a key component in determining the quality of our lives. Today, people are concerned about the quality of the water they drink. Although water covers more than 70% of the Earth, only 1% of the Earth's water is available as a source of drinking. Yet, our society continues to contaminate this precious resource. Water is known as a natural solvent. Before it reaches the consumer's tap, it comes into contact with many different substances, including organic and inorganic matter, chemicals, and o ther contaminants. Many public water systems treat water with chlorine to destroy disease-producing contaminants that may be present in the water. Although disinfection is an important step in the treatment of potable water, the taste and odor of chlorine is objectionable. And, the disinfectants that are used to prevent disease, can create byproducts which may pose significant health risks. Today, drinking water treatment at the point-of-use is no longer a luxury, it is a necessity! Consumers are taking matters into their own hands and are now determining the quality of the water they and their families will drink by installing a drinking water system that will give them clean, refreshing, and healthier water.
Properties: The freezing point of water is 0° C (32° F), and its boiling point is 100° C (212° F). Water reaches its maximum density at 4° C (39° F) and expands upon freezing. Water combines with salts to form hydrates and reacts with metal oxides to form acids (see Acids and Bases).
Occurrence: Water is the only substance that occurs at ordinary temperatures in all three states of matter: solid, liquid, and gas. As a solid, ice, it forms glaciers, frozen lakes and rivers, snow, hail, and frost. It is liquid as rain and dew, and it covers three-quarters of the earth's surface in swamps, lakes, rivers, and oceans. Water also occurs in the soil and beneath the earth's surface as a vast groundwater reservoir. As gas, or water vapor, it occurs as fog, steam, and clouds.
Water in Lfei: Water makes up 50 to 90 percent of the weight of living things. Protoplasm is a solution of water and fats, carbohydrates, proteins, and salts. Water transports, combines, and chemically breaks down these substances. Water also aids the metabolic breakdown of proteins and carbohydrates.
Natural Water Cycle: The continuous movement of water between the earth and the atmosphere is the hydrological cycle. Water vapor from water and land surfaces and from living cells circulates through the atmosphere and falls as rain or snow. When it reaches the earth, water either flows into streams and then into oceans or lakes, or it enters, or infiltrates the soil. Some water becomes soil moisture, which may evaporate directly or move up through the roots of plants and be released by leaves. Some water percolates downward, accumulating in the so-called zone of saturation to form the groundwater reservoir, the upper surface of which is the water table. Under natural conditions, the water table rises in response to inflowing water and then declines as water drains into natural outlets such as wells and springs.
Composition: Because water dissolves numerous substances in large amounts, pure water rarely occurs in nature. Precipitation absorbs carbon dioxide and other gases, as well as traces of organic and inorganic material from the atmosphere. Because water reacts with minerals in the soil and rocks, surface and groundwater may contain many different dissolved substances. Surface waters may also contain domestic sewage and industrial wastes. Groundwater from shallow wells may contain nitrogen compounds and chlorides, but water from deep wells generally contains only dissolved minerals. Seawater contains many soluble compounds in addition to salt.
Water Purification: Impurities are removed from water by screening, sedimentation, filtration, chlorination, or irradiation. See also Sewage Disposal. Aeration saturates water with air, usually by spraying fountains of water into the air. Aeration removes odors and tastes caused by decomposing organic matter, industrial wastes, and some gases. Various salts and metals cause hardness in water. Hardness may be removed by boiling, by adding sodium carbonate and lime, or by filtering through natural or artificial zeolites.
Water Desalinization: Three desalinization processes, which involve evaporating salt water and then condensing the resulting steam, are known as multiple-effect evaporation, vapor-compression distillation, and flash evaporation. Freezing is another desalinization method, based on the different freezing points of fresh and salt water. Ice crystals are separated from the salt brine, washed, and melted into fresh water. In reverse osmosis, pressure forces fresh water through a membrane that does not allow minerals to pass. In electrodialysis, the positive and negative ions of the dissolved salt are removed from water by an electric current through special membranes.
These fine drinking water systems reduce a wide range of contaminants of health concern for a low cost per gallon. The superior effectiveness of solid carbon block systems is confirmed by testing and certification by NSF International; independent laboratory tests; certification by the State of California Department of Health Services; and more importantly, by the more than two million satisfied customers throughout the world. The performance of the solid carbon block filter technology exceeds that of all other filter types and meets only the highest standards for
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