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Edexcel - Chemistry Unit 2 - 4 June 2013 Watch

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    (Original post by James A)
    Thanks

    Wbu? You in year 12?
    Doing AS. Year 11. It was SUCH a pain at first 'cause of the huuuuge jump from IGCSEs! But now Im getting the hang of it
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    (Original post by James A)
    SO2

    O=S=O
    :yep:
    But doesn't the link suggest O<-S=O :confused:
    http://diewissenschaft.wiki.hci.edu....ur_dioxide.png
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    (Original post by posthumus)
    But doesn't the link suggest O<-S=O :confused:
    http://diewissenschaft.wiki.hci.edu....ur_dioxide.png
    http://en.wikipedia.org/wiki/Sulfur_dioxide

    It's definitely two double bonds, sometimes the dot and cross don't add up to the final structure. Check with your teacher when your back at school perhaps?
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    (Original post by Zoeyyy)
    Doing AS. Year 11. It was SUCH a pain at first 'cause of the huuuuge jump from IGCSEs! But now Im getting the hang of it
    iGCSE's eh? You're not a UK student?
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    (Original post by James A)
    http://en.wikipedia.org/wiki/Sulfur_dioxide

    It's definitely two double bonds, sometimes the dot and cross don't add up to the final structure. Check with your teacher when your back at school perhaps?
    Same link you gave, check down, under structure and bonding...
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    (Original post by James A)
    iGCSE's eh? You're not a UK student?
    Nope, mid east
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    (Original post by Relaxedexams)
    Same link you gave, check down, under structure and bonding...
    Keyword: Resonance.

    The definitive structure is classed as two double bonds, but because it has a resonance, it's classed as two double bonds.
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    (Original post by James A)
    Keyword: Resonance.

    The definitive structure is classed as two double bonds, but because it has a resonance, it's classed as two double bonds.
    Right, so is O-S=O wrong, or is it a must to add two double bonds. After all the pi bond is resonant, therefore wouldn't it make more sense if the structure was drawn with one double bond at a time?
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    (Original post by James A)
    http://en.wikipedia.org/wiki/Sulfur_dioxide

    It's definitely two double bonds, sometimes the dot and cross don't add up to the final structure. Check with your teacher when your back at school perhaps?
    Ah I thought it might be because of resonance !

    It's a bit like Ozone... O=O=O

    Thanks for the link
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    (Original post by Relaxedexams)
    Right, so is O-S=O wrong, or is it a must to add two double bonds. After all the pi bond is resonant, therefore wouldn't it make more sense if the structure was drawn with one double bond at a time?
    It's hard to describe, but the molecule alternates in resonance. At one split second, it's O-S=O, the next split second it's O=S-O, therefore, strictly speaking we can't really say the fixed structure is O-S=O, but instead the scientists just assign it as O=S=O. I hope that's a little clearer now.

    But when you study unit 5, you will come across benzene and the resonance structure is has.

    :yy:
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    (Original post by posthumus)
    Ah I thought it might be because of resonance !

    It's a bit like Ozone... O=O=O

    Thanks for the link
    Exactly, Ozone has resonance too, good spot !!

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    Oh so NOW it decides to approve my posts from 14 hours ago.. LOL!
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    Can anyone recommend a good text book for units 4,5 and 6!


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    (Original post by James A)
    It's hard to describe, but the molecule alternates in resonance. At one split second, it's O-S=O, the next split second it's O=S-O, therefore, strictly speaking we can't really say the fixed structure is O-S=O, but instead the scientists just assign it as O=S=O. I hope that's a little clearer now.

    But when you study unit 5, you will come across benzene and the resonance structure is has.

    :yy:
    Thanks for clearing it up
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    (Original post by Relaxedexams)
    Right, so is O-S=O wrong, or is it a must to add two double bonds. After all the pi bond is resonant, therefore wouldn't it make more sense if the structure was drawn with one double bond at a time?
    Check this video tut. It helps a lot.
    http://www.youtube.com/watch?v=yxQ2brIlIC0
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    (Original post by NilFBosh)
    Can anyone recommend a good text book for units 4,5 and 6!


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    http://www.cgpbooks.co.uk/pages/prod...mistry_edexcel
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    is the fraser book good?
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    (Original post by NilFBosh)
    is the fraser book good?
    Some people find the facer book easier to understand - some hate it

    Personally I find it easier to read because I'm used it by now

    It has a lot of unnecessary information in it though!
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    Isnt there a student book? And whats the diff between this and the student book?
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    (Original post by NilFBosh)
    Isnt there a student book? And whats the diff between this and the student book?
    The student book is full of crap. Nothing in it for the exams. "How science works" is the only thing you need to read in it. This book is a better guide.
    ....lol big difference.
 
 
 
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