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Homework Help: Ph calculations

  1. Nov 5, 2006 #1
    I know what the formal definition of ph is, and I am comfortable with logarithms, anti-logs, and the laws of exponents. Still, I get confused doing actual calculations and would greatly appreciate your input on the following:
    Suppose something has a ph of 3.5-How do you calculate the hydrogen ion concentration?
    Suppose something has a ph of 7.2- How do you calculate the hysdrogen ion concentration?
    Suppose that something has a hydrogen ion concentration of 2.8 times ten to the minus 15-How do you calculate its ph?
    Suppose that something has a hydrogen ion concentration of 3.6 times ten to the minus 9-How do you calculate its ph?:surprised Yonderboy98
     
  2. jcsd
  3. Nov 5, 2006 #2

    Borek

    User Avatar

    Staff: Mentor

    [H+] = 10-pH
    pH = -log([H+])

    That's all.
     
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