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Acid/Base pH

  1. Aug 16, 2005 #1
    when you add 10.0 mL of 1.0M HClO4 into 990.0mL water, the pH changes by 2.
    how would you find the change in pH?
  2. jcsd
  3. Aug 17, 2005 #2


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    1. Write out the expression that defines pH
    2. Assume HClO4 is close to 100% dissociated in solution
    3. From the original concentration of HClO4, find [H+] and calculate the original pH from this

    4. Calculate the new (diluted) concentration of HClO4 (molarity = number of moles/volume of solution)
    5. Using the new value of [H+], calculate pH again.
    6. Subtract from the original number to find the difference.
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