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Homework Help: Water molecule

  1. Oct 24, 2007 #1
    Why does water angled 104.45° ?
     
  2. jcsd
  3. Oct 24, 2007 #2

    Gokul43201

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    Because the O-atom is sp3 hybridized, and the repulsion from non-bonding electron pairs is greater than that from bonding electron pairs.
     
  4. Oct 25, 2007 #3

    jim mcnamara

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    Gokul - good answer. But it doesn't totally explain the divergence of the 104.45 degree angle from the expected 109.47 degree angle - this explains why (I think):

    http://xnet.rrc.mb.ca/rcharney/The%20water%20molecule.htm [Broken]
     
    Last edited by a moderator: May 3, 2017
  5. Oct 26, 2007 #4

    Gokul43201

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    Jim, the divergence was traditionally explained in terms of a greater delocalization of the lone pairs causing the bond angle to be smaller that the symmetric angle - this is what I stated above. However, the information in your reference suggests there is now good reason to believe that in fact, the 2s orbital is unhybridized and the 105 deg = 90 deg + steric repulsion from H atoms.

    Thanks for the link.
     
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