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    http://www.chemguide.co.uk/atoms/bonding/shapes.html

    Scroll down to "A tricky example, ClF3"

    This website states that the second example has 6 lone pair - bond pair repulsions due to three lone pair - bond pair repulstions for each lone pair.

    I can only see 4 lone pair - bond pair repulstions I think the other two are a mistake

    am i right or are they right. If they are right, why?
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    They're saying that the two lone pairs each repel three fluorines, but that the repulsion cancels out.
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    (Original post by jsmith6131)
    http://www.chemguide.co.uk/atoms/bonding/shapes.html

    Scroll down to "A tricky example, ClF3"

    This website states that the second example has 6 lone pair - bond pair repulsions due to three lone pair - bond pair repulstions for each lone pair.

    I can only see 4 lone pair - bond pair repulstions I think the other two are a mistake

    am i right or are they right. If they are right, why?
    The website is simplifying by considering only bonding pairs at 90º to cause bond repulsion. (A lone pair at 120º to a bond pair does not count)
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    I presume we were looking at the second example:
    if so I cant see where the 3rd repulsion is for the lone pair

    EDIT: The confusion on your behalf may also be what I mean by second.
    There are three pictures and each is dealt with beneath.
    I am refering to the first picture amongst the three pictures but the one that is dealt with second

    In spite of this neither the first or second picture (in the group of three) seems to have a lone pair repelling three Flourines
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    (Original post by jsmith6131)
    I presume we were looking at the second example:
    if so I cant see where the 3rd repulsion is for the lone pair

    EDIT: The confusion on your behalf may also be what I mean by second.
    There are three pictures and each is dealt with beneath.
    I am refering to the first picture amongst the three pictures but the one that is dealt with second

    In spite of this neither the first or second picture (in the group of three) seems to have a lone pair repelling three Flourines
    You're damn tootin righty I don't know which you are referring to ...



    Is it pic1, pic2 or pic 3?
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    (Original post by charco)
    You're damn tootin righty I don't know which you are referring to ...



    Is it pic1, pic2 or pic 3?
    The question relates to pic 1
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    (Original post by jsmith6131)
    The question relates to pic 1
    OK

    In pic 1 both lone pairs at in the axial positions.

    This means that both lone pairs are at right angles to all three fluorines.

    There are three strong repulsions from 'below' and three from 'above', making six repulsions in total.

    However, the repulsive effects from 'below' are cancelled out by identical (but opposite) repulsive effects from 'above', leaving the orientation of the trigonal plane unaffected.
 
 
 
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