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Lerete

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MOR THEO pH pH describes the acidity or alkalinity of water and represents the balance between hydrogen ions (H+ ) and hydroxide ions (OH! ) in water. The value for pH is expressed on a scale ranging from 0 to 14. Solutions with more H+ than OH! ions have a pH value lower than 7 and are said to be acidic. Solutions with pH values higher than 7 have more OHthan H+ ions and are said to be basic, or alkaline. If the pH value is 7, the solution is said to be neutral (an equal number of H+ and OH! ions) and is neither acidic nor alkaline. It is important to note that the pH scale is logarithmic. This means that each step on the scale represents a tenfold change in the H+ concentration. For example, water with a pH of 5 has ten times the number of H+ ions than water with a pH of 6 and is ten times more acidic. pH and Water Water with a pH of less than 4.8 or greater than 9.2 can be harmful to aquatic life. Most freshwater fish prefer water with a pH range between 6.5 and 8.4 (colored band on the graph). The pH is also a useful indicator of the chemical balance in water. A high or low pH will adversely affect the availability of certain chemicals or nutrients in the water for use by plants.
ALKALINITY: [120-170 mg/L] The alkalinity of a water is a measure of its capacity to neutralize acids. Although many materials may contribute to the alkalinity of water, most of the alkalinity in natural water is caused by the presence of hydroxides, carbonates, and bicarbonates. Carbonates and bicarbonates are common to most waters because carbonate materials are abundant in nature, whereas the presence of hydroxides is usually due to water treatment or contamination. Because these substances act as buffers to resist change in pH, alkalinity can also be viewed as a measure of a water’s buffering capacity. Alkalinity impacts and is impacted by chemical and biological systems of natural waters. pH: [8.3] The pH value of water, on a scale of 0 to 14, measures the concentration of hydrogen ions. Pure distilled water is considered neutral, with a pH reading of 7. Water is basic if the pH is greater than 7; water with pH of less than 7 is considered acid. For every one unit change in pH there is approximately a ten-fold change in how acid or basic the sample is. Most valuable species, such as brook trout, are sensitive to changes in pH; immature stages of aquatic insects and immature fish are extremely sensitive to low pH values. Very acidic lakes and streams cause leaching of heavy metals into the water.

CHLORIDE: High concentrations of chloride ions may result in an objectionable salty taste to water and the corrosion of plumbing in the hot water system. High chloride waters may also produce a laxative effect. An upper limit of 250 mg/L has been set for the chloride ions, although at this limit few people will notice the taste. Higher concentrations do not appear to cause adverse health effects. An increase in the normal chloride content of your water may indicate possible pollution from human sewage, animal manure or industrial wastes.
Total Hardness: Hardness is the property which makes water form an insoluble curd with soap and is primarily due to the presence of Calcium and Magnesium. Waters which are very hard have no known adverse health effects and may be more palatable than soft waters. Hard water is primarily of concern because it requires more soap for effective cleaning, forms scum and curd, causes yellowing of fabrics, toughens vegetables cooked in the water and forms scale in boilers, water heaters, pipes and cooking utensils. The hardness of good quality water should not exceed 270 mg/L (15.5 grains per gallon) measured as calcium carbonate. Water softer than 30-50 mg/L may be corrosive to piping depending on pH, alkalinity and dissolved oxygen.
Total HARDNESS: Hardness is the property which makes water form an insoluble curd with soap and is primarily due to the presence of Calcium and Magnesium. Waters which are very hard have no known adverse health effects and may be more palatable than soft waters. Hard water is primarily of concern because it requires more soap for effective cleaning, forms scum and curd, causes yellowing of fabrics, toughens vegetables cooked in the water and forms scale in boilers, water heaters, pipes and cooking utensils. The hardness of good quality water should not exceed 270 mg/L (15.5 grains per gallon) measured as calcium carbonate. Water softer than 30-50 mg/L may be corrosive to piping depending on pH, alkalinity and dissolved oxygen.…...

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