Is a measure of the acidity or basilica of an aqueous solution. Solutions with a pH less than 7 are said to be acidic and solutions with a pH greater than 7 are basic or alkaline. Pure water has a pH very close to 7. PH is defined as the decimal logarithm of the reciprocal of the hydrogen ion activity, ah+, in a solution. Universal indicator consists of a mixture of indicators such that there is a continuous color change from about pH 2 to pH 10. Universal indicator paper is made from absorbent paper that has been impregnated with universal indicator.
Indicator Low pH color Transition pH range High pH color Thyme Blue(first transition) Red 1. 2 – 2. 8 Yellow Methyl Red 4. 4 вЂ? 6. 2 Brotherly Blue 6. 0 – 7. 6 Blue Thyme blue (second transition) 8. 0 – 9. 6 Phenolphthalein Colorless 8. 3- 10. 0 Fuchsia In our lab , we used pH meter to calculate pH of samples. A pH meter Is an electronic device used for measuring the pH of a liquid (though special probes are sometimes used to measure the pH of semi-solid substances).
A typical pH meter consists of a special measuring probe connected to an electronic meter that measures and displays the pH reading. Color The Platinum-cobalt Scale (Opt/Co scale or Papa-Hazer Scale ) Is a color scale that was introduced in 1892 by chemist Allen Hazer(1869-1 930). The index was developed as a 1 OFF method of comparison of the intensity of yellow-tinted samples. It is specific to the color yellow and is based on dilutions of a 500 pump platinum cobalt solution.
The ASTM has detailed description and procedures in ASTM Designation 12TH, “Standard Test Method for Color of Clear Liquids (Platinum-cobalt Scale) Electrical Conductivity (SEC) The electrical conductivity of the water depends on the water temperature : the higher the temperature, the higher the electrical conductivity would be. The electrical inductively of water increases by 2-3% for an increase of 1 degree Celsius of water temperature. Many SEC meters nowadays automatically standardize the readings to ICC.
An electrical current results from the motion of electrically charged particles in response to forces that act on them from an applied electric field. Within most solid materials a current arise from the flow of electrons, which is called electronic conduction. In all conductors, semiconductors, and many insulated materials only electronic conduction exists, and the electrical conductivity is strongly dependent on he number of electrons available to participate to the conduction process.
Most metals are extremely good conductors of electricity, because of the large number of free electrons that can be excited in an empty and available energy state. In water and ionic materials or fluids a net motion of charged ions can occur. This phenomenon produce an electric current and is called ionic conduction. Dissolved Oxygen (DO) Biologically speaking, the level of oxygen is a much more important measure of water quality than fecal chloroforms. Dissolved oxygen is absolutely essential for the survival of all aquatic organisms.
Moreover, oxygen affects a vast number of other water indicators, not only biochemical but esthetics ones like the odor, clarity and taste. Consequently, oxygen is perhaps the most well-established indicator of water quality. Adequate dissolved oxygen is necessary for good water quality. Oxygen is a necessary element to all forms of life. Natural stream purification processes require adequate oxygen levels in order to provide for aerobic life forms. As dissolved oxygen levels in water drop below 5. MGM/l, aquatic life is put under stress. The lower the concentration, the greater the stress. Oxygen levels that remain below 1-2 MGM/l for a ewe hours can result in large fish kills. Total dissolved gas concentrations in water should not exceed 110 percent. Concentrations above this level can be harmful to aquatic life. Chloride (CLC-) Almost all natural waters contain chloride and sulfate ions. Their concentrations vary considerably according to the mineral content of the earth in any given area.
In small amounts they are not significant. In large concentrations they present problems. Usually chloride concentrations are low. Sulfates can be more troublesome because they generally occur in greater concentrations. Low to moderate concentrations of OTOH chloride and sulfate ions add palatability to water. In fact, they are desirable for this reason. Excessive concentrations of either, of course, can make water unpleasant to drink. Chloride is commonly found in streams and wastewater.
Chloride may get interfaces water from several sources including: вЂў Wastewater from industries and municipalities вЂў Road salting вЂў Agricultural runoff вЂў Produced water from gas and oil wells Salinity Salinity is the saltiness or dissolved salt content of a body of water . Salinity is an important factor in determining many aspects of the chemistry of natural waters and f biological processes within it, and is a thermodynamic state variable that, along with temperature and pressure, governs physical characteristics like the density and heat capacity of the water.
Salinity in rivers, lakes, and the ocean is conceptually simple, but technically challenging to define and measure precisely. Conceptually the salinity is the quantity of dissolved salt content of the water. Salts are compounds like sodium chloride, magnesium sulfate, potassium nitrate, and sodium bicarbonate which dissolve into ions. Operationally, dissolved matter is defined as that which can ass through a very fine filter . Salinity can be expressed in the form of a mass fraction, I. E. The mass of the dissolved material in a unit mass of solution.
Total Dissolved solid (ADS) Total Dissolved Solids (ADS) are the compounds in the water that cannot be removed by a traditional filter. ADS are made up of salts or compounds which dissociate in water to form ions. This means that a salt has two parts, one with a positive charge and one with a negative charge, which separate and mix with the water (H2O) molecules. Total dissolved solids (ADS) is a measure of the combined content of all inorganic and organic substances contained in a liquid in molecular, unionized or micro-granular suspended form.
Primary sources for ADS in receiving waters are agricultural and residential runoff, leaching of soil contamination and point source water pollution discharge from industrial or sewage treatment plants. The most common chemical constituents are calcium, phosphates, nitrates, sodium, potassium and chloride, which are found in nutrient runoff, general storm water runoff and runoff from snowy climates where road De-icing salts are applied. The chemicals may be actions, anions, molecules or agglomerations on the order of one thousand or ewer molecules, so long as a soluble micro-granule is formed.
More exotic and harmful elements of ADS are pesticides arising from surface runoff. Certain naturally occurring total dissolved solids arise from the weathering and dissolution of rocks and soils Total Suspended Solid (TTS) TTS are solid materials, including organic and inorganic, that are suspended in the water. These would include silt, plankton and industrial wastes. High concentrations of suspended solids can lower water quality by absorbing light. Waters then become warmer and lessen the ability of the water to hold oxygen necessary for aquatic life.
Because aquatic plants also receive less light, photosynthesis decreases and less oxygen is produced. The combination of warmer water, less light and less oxygen makes it impossible for some forms of life to exist. Suspended solids affect life in other ways. They can clog fish gills, reduce growth rates, decrease resistance to smother fish eggs and those of aquatic insects, as well as suffocate newly-hatched larvae. The material that settles also fills the spaces between rocks and makes these microcircuits unsuitable for various aquatic insects, such as mayfly nymphs,