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Chemistry

Chemistry. Aiza, Em, Katrina, Kierstin, Sarah. 1. Test Results. Averages. 2. Titration. Calibration Acquire known concentration Ensure results match what they theoretically should be Put stream water in titration tube Fill the titrator syringe with titration solution

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Chemistry

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  1. Chemistry • Aiza, Em, Katrina, Kierstin, Sarah 1

  2. Test Results Averages 2

  3. Titration • Calibration • Acquire known concentration • Ensure results match what they theoretically should be • Put stream water in titration tube • Fill the titrator syringe with titration solution • Drop solution into titration tube slowly until water reaches indicating color • Count how many drops used 3

  4. Axial Colorimeter • Calibration • Add a few drops of solution to a tube of stream water • Qualitatively determine by color comparison how much of the solute is in there • This gives you quantitative data 4

  5. PH Calibration • Two known solutions • Compare and adjust measuring instrument 5

  6. Nitrates • Colorimeter test used • Wast produced by humans/animals • Factors: • DO decrease, nitrate increases • Aerobic bacteria breaks down large proteins • Optimal: 0.01-3.0 mg/L(the lower the better) • Affects: High nitrates cause high pH levels • Nitrogen needed by all life forms to make proteins, grow, and reproduce • High nitrate causes illness of aquatic animals 6

  7. Alkalinity • Titration • Factors: • Limestone and soil • Bicarbonate ions and carbonic acids • Optimal: 100-250 mg/L • Affects: • Buffers water against sudden pH changes • Tow high=cloudy=hinders growth 7

  8. Hardness • Titrate • Factors: • Dissolved salts (calcium and manganese) • Rocks-Limestone, dolomite, gypsum, others • Optimal: 10-1700 mg/L • Affects: • Mineral deposits=pipes • Aquatic plant’s cell walls, bones of animals • Magnesium-Nutrient for plants • High calcium levels in eutrophic waters 8

  9. pH • Probe used (calibrated with solutions) • Factors: • acid rain • Rocks or soil in surrounding watershed • Decomposing waste • Optimal- pH of 7 (neutral) • Affects: High pH kills animals (or low pH) • Ph increases/decreases-ecosystem adapts • Can cause toxic water • Young aquatic animals are very sensitive to low pH, older more mature animals can adapt slowly 9

  10. Phosphate • Colorimeter • Factors: • Limits plants growth, comes from detergents • Optimal: should not exceed 0.05mg/L • Affects: • Phosphates increase causing excess plant growth and decomposition • Aerobic bacteria will thrive and consume oxygen, DO levels decrease and affect the quality of animal life 10

  11. Ammonia Nitrogen • Colorimeter • Factors: • Decaying plants and animals • Animal and industrial waste • Agricultural runoff • Optimal: Do not exceed 0.05 mg/L • Affects: High levels toxic to aquatic life • High nitrification, DO level lowered • Low nitrification levels, limit plant and algal growth 11

  12. DO • Titration • Factors: • Season, weather, temperature, time of day • Over abundance of organic material • Amount of thermal pollution • Optimal: 2-18 mg/L (9-10 mg/L is very good) • Affects: • Change the aquatic plants (if too low) • Cause photosynthesis to increase or decrease • Plants bloom or die • Species suffer with low amounts of DO 12

  13. What factors influence amount of chemical? • Nitrates: • plant or animal decomposition causes lowered DO which in turn increases nitrate levels; aerobic bacteria break proteins down into ammonia which becomes nitrates and nitrites; leaking septic filters, fertilizer runoff, or improperly treated wastewater; animal feces in water (especially geese and ducks) • Ammonia Nitrogen: • decaying plants and animals, animal waste, industrial waste effluent, agricultural runoff, nitrogen in the atmosphere 13

  14. Factors, Continued • Phosphate: • high levels of phosphate come from surface runoff or bank erosion (specifically septic tank leaks, fertilizer runoff, or improperly treated sewage); many detergents contained phosphates at one time; high nitrate levels can cause high phosphate levels • Alkalinity: • bicarbonate ions come from the dissolution of carbonates by carbonic acids; sources leach from limestone and soil, and minerals like dolomite and calcite; high levels of precipitation lowers alkalinity 14

  15. Factors, Continued • Hardness: • hardness is caused by various dissolved calcium, magnesium, or iron salts, mostly through the leaching of rocks • PH • near neutral is best (pH of 7); 6.5 to 7.5 is considered excellent, but below 5 or above 8.5 is very harmful to most organisms 15

  16. Factors, Continued • DO: • warmer water holds less DO than cold water (and this can vary based on the time of day, season, or the weather); excess organic matter is eaten up by bacteria and algae, which lower the DO; dissolved oxygen is less soluble in low pressure (at high altitudes); aeration (wind, thermal upwelling, or water flowing over rocks) increases DO 16

  17. What is the optimal amount of the chemical? • Nitrates: • 1.0 mg/L is considered excellent, 5.0 mg/L is considered unsafe to drink, and over 10.0 mg/L can decrease red blood cells’ ability to carry oxygen and can cause blue baby syndrome • Ammonia Nitrogen: • less than 0.5mg/L • Alkalinity: • 100 to 250 mg/L is considered normal, and freshwater has an average of 20 to 200 mg/L 17

  18. Optimal, Continued • Phosphate: • in a stream draining into a river, the phosphate levels should not be above 0.025 mg/L in the stream or above 0.1 mg/L in the river; more than 0.1 mg/l causes unnatural rates of eutrophication • Hardness: • fewer than 10 grains per gallon results in sparse plant/animal life; typical freshwater ranges from 4 to 100 grains per gallon 18

  19. Optimal, Continued • PH: • near neutral is best (pH of 7); 6.5 to 7.5 is considered excellent, but below 5 or above 8.5 is very harmful to most organisms • DO • 5 to 6 mg/L is best for supporting diverse aquatic systems; higher (9 to 10) is better than lower (3) 19

  20. What factors are affected by the amount of chemical? • Nitrates: • nitrate increase usually results in phosphate increase and DO decrease; plants and animals need nitrates to grow, produce proteins, and reproduce; high levels of nitrite can cause serious diseases in fish • Ammonia Nitrogen: • as a nutrient for algae and aquatic plants, excess ammonium can lead to eutrophication or even toxicity to aquatic organisms near the water’s surface, and also lowered DO; low ammonium can limit plant and algae growth 20

  21. Affects, Continued • Phosphate: • phosphates contribute to eutrophication (and algal blooms), and therefore low DO levels; this also causes a blockage of sunlight and an increase in water temperature; plants use phosphorous to grow and animals use it to conduct metabolic reactions and to produce bone • Alkalinity: • alkalinity can be a buffer in water against sudden changes in pH; low alkalinity can cause water to become acidic, which harms developing aquatic life; high alkalinity can raise the pH level (which kills fish) or make the water turbid (which hurts bottom-dwelling organisms) 21

  22. Affects, Continued • Hardness: • hard water can leave deposits and crusting in pipes/boilers/cooking utensils, soaps and detergents don’t lather as well in hard water (which increases soap/detergent consumption); calcium is a key feature in plant cell walls and bones/shells of aquatic animals; calcium and magnesium are needed to support aquatic life, and magnesium in found in chlorophyll 22

  23. Affects, Continued • PH: • most aquatic organisms require specific pH levels and suffer without them; animal larvae and eggs have very narrow pH requirements; very acidic water can cause the release of heavy metals into water, which can get caught on fish gills 23

  24. Affects, Continued • DO • high water temperature increases photosynthesis rates, which use up DO; mayfly nymphs, stonefly nymphs, caddisfly larvae, beetle larvae, pike, bass, and trout require an environment with lots of dissolved oxygen 24

  25. How can we reduce dangerous chemical levels of the Leibert? • Nitrate, ammonium nitrogen, phosphate, alkalinity, and DO are all within a very healthy range. Hardness seems a little bit high and pH is almost too high: hardness is probably due to the limestone area around the creek, but it isn’t such a problem in creeks, although harder tap water might lead to more soap or detergent use, which may accidently get into the stream (not so likely). The level of pH should be at least maintained, but it is probably also due to limestone. 25

  26. Outside Affects on the Leibert • Leaking septic tanks • Possible runoff • Trash deposited by people in community park • Positive readings therefore little outside effects 26

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