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question from OAT Practice Exam

Discussion in 'DAT Discussions' started by topdent1, Jun 17, 2008.

  1. topdent1

    2+ Year Member

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    Chlorine bleaches are solutions that contain approximately 5% NaClO. These solutions are

    A. slightly acidic.
    B. strongly acidic.
    C. neutral.
    D. slightly basic.
    E. strongly basic.


    The answer is D. Care to explain why? I though ClO4 was a strong acid.
     
  2. osimsDDS

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    NaClO is a salt (conjugate base of a weak acid HClO)...Basically you started out like this:

    HClO (hypochlorous acid) + NaOH -----> NaClO (conjugate base of a weak acid) + H20

    The solution consists of HClO which is a weak acid and NaOH which is a strong base...weak acid + strong base = basic solution

    Now to distinguish between D and E, slightly basic vs strongly basic I have no idea how you would be able to know that...maybe someone else can help
     
  3. Glycogen

    2+ Year Member

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    I chose d b/c as you mentioned it is a weak base,this (being weak base) and mentioning 5% will let us to conclude that it is slightly basic,I think.
     
  4. vvvv

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    ClO- will hydrolyze water. ClO- + HOH = HClO + OH- this is slightly basic...
     
  5. shoombol tallah

    shoombol tallah Big Boy
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    I think the OP is confusing ClO4(Perchlorate) with ClO(hypochlorite) . If the solution formed HCl04 instead of HClO then your right it would have been acid. When comparing oxyacids the more oxygens you have the strong the acid. For exampl HClO4>HClO3>HCl02>HClO. Hope that helps :)
     

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