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Homework Help: Acids and bases

  1. May 6, 2007 #1
    An increase in the OH- in a solution would result in

    an increase in alkalinity (baseness).

    an increase in acidity.

    a pH of 7.

    a decrease in pH.

    i think it would be - an increase in alkalinity, but im not sure
  2. jcsd
  3. May 6, 2007 #2


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    When you add OH- to a solution, what does it bond with (i.e. remove some of from the solution)?

    And what does that have to do with the definition of pH?

    You're correct, but you should be able to be more confident in your guess
  4. May 6, 2007 #3
    Thanks for the help!
  5. May 9, 2007 #4
    pH is the negative of the log of the concentration of H3O+ ions (sometimes also called H+ ions) so the formula is:
    pH = -log[H3O+]

    The same is true for pOH except this time you are looking at the concentration of OH- ions:
    pOH = -log[OH-]

    And always remember pH + pOH = 14
    so yes, if you increase the OH- ion concentration, you increase Alkalinity (and decrease acidity)
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