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    hi guys,
    i have problems with figuring out the molecular shapes of all the polyatomic ions. i'm ok with the compound ones,but totally have no clue for the ions. please help.

    thanks
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    (Original post by kingsclub)
    hi guys,
    i have problems with figuring out the molecular shapes of all the polyatomic ions. i'm ok with the compound ones,but totally have no clue for the ions. please help.

    thanks
    pretty much works the same way too, consider number of bonding pairs and lone pairs, but be aware of resonance delocalisation.

    ie carbonate, CO3 2- is trigonal planar, SO42- is tetahedral, etc
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    but i'm totally freaked out by the number up there... actually, what do 2- or 2+ mean? i always mixed up which one "borrows" the electrons...
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    (Original post by kingsclub)
    but i'm totally freaked out by the number up there... actually, what do 2- or 2+ mean? i always mixed up which one "borrows" the electrons...
    If the structure carries a 2- charge it means that it has two 'extra' electrons that the atoms making the structure up didn't have.

    If it has a 2+ charge it means that two electrons have been lost from the atoms making up the structure.
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    (Original post by charco)
    If the structure carries a 2- charge it means that it has two 'extra' electrons that the atoms making the structure up didn't have.

    If it has a 2+ charge it means that two electrons have been lost from the atoms making up the structure.
    oh, i kind of get it...
    is that why the metal cations have positive charges because they have to lose electrons to obtain an octet structure?
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    (Original post by kingsclub)
    oh, i kind of get it...
    is that why the metal cations have positive charges because they have to lose electrons to obtain an octet structure?
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    hurray
    thanks a lot!
 
 
 
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