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Overall, H2O More Negative Than Positive?

  1. Oct 22, 2011 #1

    jaketodd

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    There is a link to a picture below. It shows two Hydrogen atoms on the same side of an Oxygen atom (both on the lower half of the Oxygen atom). Because the distribution of Hydrogen in H2O is not symmetrical, does that mean that, on average, the H2O molecule is more negatively charged in its interactions with matter? I have read that the molecule has a positive end and a negative end. Is the negative end more dominant, overall?

    The image can be found at the top right of this page: http://en.wikipedia.org/wiki/Water_%28molecule%29" [Broken]

    Thanks,

    Jake
     
    Last edited by a moderator: May 5, 2017
  2. jcsd
  3. Oct 22, 2011 #2
    No. A water molecule contains the same number of protons and electrons, therefore it is neutral. The fact that they are distributed unevenly makes for some interesting chemistry, but does not change the fact that the molecule, as a unit, is neutral.
     
  4. Oct 22, 2011 #3

    Redbelly98

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    No, a water molecule is electrically neutral, overall. It has 10 protons and 10 electrons, so the net charge is zero.

    EDIT: Not surprisingly, MrSpeedyBob was faster in replying than I was. :smile:
     
  5. Oct 22, 2011 #4

    jaketodd

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    Perhaps you are neglecting the positioning of the Hydroden atoms to the Oxygen atom? After all, forces do diminish with distance.

    Jake
     
  6. Oct 22, 2011 #5

    jaketodd

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    Like here: "Molecules that have 'low' symmetry will always have at least a small dipole moment and therefore be referred to as polar. Examples of such low symmetry molecular shapes include: Bent molecules, eg. water"

    Source: http://itl.chem.ufl.edu/2041_u01/lectures/lec_16.html" [Broken]
     
    Last edited by a moderator: May 5, 2017
  7. Oct 22, 2011 #6

    uart

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    Your original question was not whether or not it had a dipole moment (which it does), but whether or not it was overall negatively charged (which it isn't). Hopefully you understand that these are two different things.
     
    Last edited by a moderator: May 5, 2017
  8. Oct 23, 2011 #7

    Redbelly98

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    Forces between charges do diminish with distance, but the amount of charge doesn't.
     
  9. Oct 23, 2011 #8
    No, it is neutral, its net charge is zero. That is why we write it as H2O, which is the same than [ H2O ]+0 or [ H2O ]-0

    in the liquid phase molecules dissociate into [ H3O ]+ and [ OH ]- each of them charged, but the net charge of the fluid is zero of course.
     
    Last edited by a moderator: May 5, 2017
  10. Oct 23, 2011 #9

    jaketodd

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    Thanks guys,

    Jake
     
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