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PH of HCl solution as a function of volume.

  1. Feb 27, 2012 #1
    1. The problem statement, all variables and given/known data
    You have a 1L of a 2M HCl solution. Assume that the HCl completely ionizes.
    a) Calculate the pH of the solution right now.
    b) You now add V litres of water to the solution.
    Find the pH of the new dilute solution in terms of V.

    2. Relevant equations
    pH = -log[H]

    3. The attempt at a solution
    a) pH = -log(2) which is interestingly a negative number so I hope this is correct.
    b) I'm not sure how you would do this part. Do we just find the new concentration in terms of V and then find the negative log of that? Don't we have to consider the autoionization of water?


  2. jcsd
  3. Feb 28, 2012 #2


    User Avatar

    Staff: Mentor

    Yes, negative pH is possible.

    Check the link I posted in your other thread for the way pH should be calculated. And read about dilution calculation.
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