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Help with chemistry question?

  1. Sep 23, 2009 #1
    Help with chemistry question????

    Arrange the following bases in order of their tendency to combine with protons, putting the strongest base first:
    NH3, H2O, OH-, CH3COO- (acetate ion), Br-.
    NH3 Kb = 1.8 X 10-5
    CH3COOH Ka = 1.8 X 10-5
     
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  3. Sep 23, 2009 #2
    Re: Help with chemistry question????

    First of all, do you know the definition of strong bases vs. weak bases? Hint: separate the ionic compounds from the molecular compounds, and go from there.
     
  4. Sep 24, 2009 #3

    Borek

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    Re: Help with chemistry question????

    I am not sure how this hint is going to work. But starting with definition will definitely help.

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  5. Sep 24, 2009 #4
    Re: Help with chemistry question????

    I meant that strong bases are strong electrolytes, so separating them into ionic and molecular will give two groups, one of strong bases and one of weak. For me, it's easier to break things down into subgroups like this. Also, this is the best advice I could think to give, since pKa doesn't seem to be mentioned.
     
  6. Sep 24, 2009 #5

    Borek

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    Re: Help with chemistry question????

    OK, I have classified both Br- and OH- as strong electolytes, does it mean they will be both on the same end of 'basicity' scale?

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    methods
     
  7. Sep 24, 2009 #6
    Re: Help with chemistry question????

    I see what you mean. My mistake. I'm still learning some of this myself, and I suppose what I said wasn't the best way to go about this problem. Sorry about that, disregard what I said before.
     
  8. Sep 24, 2009 #7

    Borek

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    Re: Help with chemistry question????

    Don't worry, the only way to not make any mistakes is to not do anything :grumpy:

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    methods
     
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