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ph question

Discussion in 'DAT Discussions' started by theedaddy77, Jun 3, 2008.

  1. theedaddy77

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    If you have 4m 40ml of Nitic acid and 2m 40ml of NaOH what is ph of final solution??????/
    i know this sounds basic but if someone can explain how they got to there answer that would be amazing!!
     
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  3. TempleDMDKrazd

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    are you talking about molality (m) or molarity (M)?
     
  4. doc toothache

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    It will take 20 ml of 4 m nitric acid to neutralize 40ml of 2m NaOH, leaving 20ml of 4 m acid. Since the final volume will be 80 ml, then

    m1v1= m2v2
    4x20= m2x80
    m2= 1
    A 1 molar nitric will have a pH of zero.
     
  5. osimsDDS

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    wow doc you just used plain old logic for that one i love it...faster and simpler than just plugging in numbers and doing a crap load of math, very nice
     
  6. theedaddy77

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    hey doc u did the last step by saying 1 M of a strong acid is 1M of H+ and -log 1 is 0?
     
  7. doc toothache

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    YES.
    HNO3-----> H+ + NO3-
    1m ...........1m....... 1m

    Since nitric is 100% ionized 1m nitric= 1mH+
     

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