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Which molecule most likely to deviate from ideal values?

  1. Aug 23, 2016 #1
    Hi,

    Hoping I could get some help on this one.
    How would I know what causes bond angles to deviate from the ideal values?

    I greatly appreciate any help and advice on this.

    Thanks
     
  2. jcsd
  3. Aug 23, 2016 #2

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    Anything that breaks the symmetry; 35Cl instead of 36 in a CCl4 molecule; you name it.
     
  4. Aug 23, 2016 #3
    Is there any connection between polarity?
     
  5. Aug 24, 2016 #4

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  6. Aug 24, 2016 #5
    If so, how would you compare between different molecules? Like if I were to compare which molecules deviated THE MOST from the "ideal" values...
    for example BrCl3, XeCl4, or CO
     
  7. Aug 24, 2016 #6
    does deviation correspond to the number of lone pairs on the central atom, but even then XeCl4 and BrCl3 both have 2 pairs so I'm super confused.
    Or does it have to do with location of the lone pairs?
     
  8. Aug 24, 2016 #7

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    CO? A straight line is a straight line. What are the "ideal" values for the other two? Which isotopes/isotope combinations are you considering "ideal?"
    Two pairs? What are you counting?
     
  9. Aug 24, 2016 #8
    but arent there lone pairs of electrons for central atom (either C or O) CO or do they not affect the bond angles?

    for XeCl4 and BrCl3, I am counting the number of lone pairs of electrons.
    so there would be 2 pairs of lone pairs on the central atom (Xe and Br, respectively), right?
     
  10. Aug 24, 2016 #9
    I am considering the VSEPR to be "ideal", sorry for any confusion
     
  11. Aug 24, 2016 #10
    I think I got it. It has to do with the placement of lone pair of electrons on the central atom.

    Thanks
     
  12. Aug 24, 2016 #11

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    One bond can NOT make an angle.
    Yes.
    So, that's back in fashion --- two pairs --- one on one side and the other opposite --- "pair repulsion" --- what are your thoughts?
     
  13. Aug 24, 2016 #12

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    Yes --- You're welcome.
     
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