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Water Molecule Realignment

  1. Sep 19, 2008 #1
    Ok, so, I'm doing a little project on water molecules. More specifically, on, well as the title suggests, realigning them. Now, at first, i thought it had to do with magnetism, when in fact magnetism has to do with electron spin rather than charges. As I tried using an electromagnet, for the electric field, nothing worked.

    The only thing that seemed to work at realigning the molecules was through static electricity from a glass rod or comb. However, I am not trying to redirect the movement of a stream of water, but to just rotate the molecules, in say, a jug (quasi-stationary). Any suggestions on how?

    Also, from my reading of van de graaf generators, they don't seem to have to same pulling capabilities as a comb does, with static electricity.

    Some equations pertaining to how to calculate the charge needed and force acting upon them would also be nice.
  2. jcsd
  3. Sep 22, 2008 #2


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    Yes, as you found out, a water molecule has an electric dipole moment, not a magnetic one. Thus it can be influenced by an electric field. But offhand, I don't think what you want to do is that simple - bulk water has a specific arrangement due to its hydrogen bond network. Rotating all of the molecules in place to align their dipole moments with the electric field would completely sabotage the hydrogen bonding network resulting in very unfavorable water-water interactions. Perhaps with a strong enough field, the dipole interaction would dominate the energetics, but there is nothing to fix the molecules in place, and so you would probably have a bulk migration of water molecules.
  4. Nov 21, 2008 #3
    Yes, shortly after you posted your answer, I have found similar saying on other websites. There was this one site which caught my attention on something very interesting. http://www.lsbu.ac.uk/water/magnetic.html [Broken]
    Here they say that with a sufficiently strong enough electric field, the dielectric constant of water may weaken, "due to the resultant partial or complete destruction of the hydrogen-bonded network."

    Like how you said an electric field may move bulk quantities of water, I'm going to hedge a guess that this, other effect has to do with the manipulation of the molecules, too. Can any one please elaborate on this effect?
    Last edited by a moderator: May 3, 2017
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