pH in water

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pH in water

• By Sarah Eggleston

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• pH is determined and recorded as a number between
  0 and 14.
• To determine the pH the amount of H ions found
  in the substance being tested must be measured.

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pH Scale

• An acid is when the pH level is below 7.
• The measurement for an acid is between 0 and 7.
• A base is when the pH level is above 7.
• The measurement for a base is anywhere between 7
  and 14.
• A neutral is when the pH level is 7.
• Neutral means the H and OH- ions are equal.

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• Many organisms are able to handle a wide range of
  pH.
• pH 3.0-3.5 unlikely for fish to survive more
  then a few hours.
• 3.5-4.0 lethal to salmonids
• 4.0-4.5 lethal to all fish, most frogs, insects
  absent
• 4.5-5.0 lethal to Mayfly and many insects.
• 5.0-5.5 bottom dwelling bacteria die
• 6.0-6.5 not likely lethal to fish
• 6.5-8.2 optimal to most organisms
• 8.2-9.0 may not directly hurt fish but indirectly
  begin to
• 9.0-10.5 harmful to salmonids, lethal if present
  long
• 10.5-11.0 lethal to salmonids
• 11.0-14.0 lethal to all fish or organisms

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Sources of pH

• Strong acid sources with pH of 4-5 leaves and
  leaf-mold of oak, beech, chestnut, blueberry,
  huckleberry, laurel, azalea, and rhododendron.
  Needles of hemlock, spruce, fir, and pine.
  Cottonseed meal and apple pomace.
• Moderate acid sources with pH of 5-6 leaves and
  leaf-mold of red maple and most birches.
• Slight acid or neutral sources with pH of 6-7
  lawn clippings, garden plants, hay, ground
  corncobs. Leaves of hickory, butternut, ash, most
  maples, elm, dogwood, poplar, basswood, willow,
  tulip-tree. Various animal manures

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pH levels around the US

• These are pH levels reported for natural water
  sources in the US.
• Rivers U.S. Potomac (MD, PA, WV) 7.8-8.4
• Ohio (OH, IN, KY) 7.0-9.0 Delaware (PA, NJ)
  7.4-7.6
• Colorado (CA, AZ) 7.7-8.5 Hillsborough (FL)
  7.1-8.2
• Snake (ID) 7.6-8.4 Little (MA) 6.2-6.5
• Rio Grande (CO, NM, TX) Arkansas (AR, OK, KS, CO)
  7.4-8.6
• Missouri (NE, KS, MO) 7.8-8.5 Brazos, Trinity,
  Colorado, Guadalupe (TX) 7.2-8.5 Mississippi(
  MN, WI, IL, MO) 7.6-8.9
• Great Lakes Lake Michigan (MI, IN, IL, WI)
  7.5-8.5
• Lake Ontario (NY) 7.9-8.3

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References

• http//www.rwater.com/education/chem.htm
• http//pmep.cce.cornell.edu/facts-slides-self/fact
  s/gen-peapp-ph.html
• http//www.rwater.com/education/chem.htm