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Name:  terri j hannam
Status: N/A
Age: N/A
Location: N/A
Country: N/A
Date: 1999 


Question:
I would like to have some information on pH, and it's relation to water quality.



Replies:
Answer pH is directly related to the hydrogen ion (H+) concentration in an aqueous (water) solution. To calculate the pH of a solution, you need to know the concentration of the H+ in molarity (i.e. moles of H+ per liter of solution).

pH = - log[H+] where [H+] = concentration of H+ in molarity. Thus if [H+] = 1.0 X 10^-3 then the pH = 3 pure water at room temperature (25 degrees C) has a pH of 7. However most water that is in contact with air will contain dissolved carbon dioxide and therefore will be slightly acidic because the dissolved CO2 will form carbonic acid... Note that in general, acid solutions have a pH < 7 and basic solutions have a pH > 7. A neutral solution will have a pH = 7. Also, note that a solution with a pH of 2 is ten times more acidic than a solution with a pH of 3.

There are pH meters which are instruments that can measure the pH of a solution. Also, one can use pH paper which can be immersed and a solution and depending on the color of the paper, the pH can be determined. Life cannot exist in highly acidic water.

Hope this helps! --- Dr. Brown



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