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    Hello everybody hope revisions going ok!

    Just wanted 2 ask, how much do you need 2 know abt alkaline half equations like how do we know when 2 use alkaline half equations
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    (Original post by Jmedi)
    Yeah it means the same thing.
    ok nice im grasping this now
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    (Original post by Aliceeee12)
    Hello everybody hope revisions going ok!

    Just wanted 2 ask, how much do you need 2 know abt alkaline half equations like how do we know when 2 use alkaline half equations
    They will tell you if it's in alkaline solution
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    (Original post by Jmedi)
    There is only ionic interaction, electrostatic forces
    The ions are perfect spheres (no charge cloud distortion)

    no covalent character
    (Original post by vish.handa)
    It assumes ions are perfectly spherical
    Assumes no covalent character
    Real value may be more negative (I think) because of any covalent character present
    (the negative thing check, It may be more positive)
    I use covalent character/interaction interchangeably - is this ok? Since I've seen on markschemes for perfect ionic model they say no covalent INTERACTION
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    so if u have more distortion of charge, then the ions are less spherical, theoretical enthalpy will be higher and there will be more covalent interactions??
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    (Original post by GO97)
    so if u have more distortion of charge, then the theoretical enthalpy will be higher and there will be more covalent interactions??
    well would it be more exo or endo, once you've got that in your head then no need to worry about remembering which way it goes , I dont know though haha hoping someone will pop up who knows
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    (Original post by vish.handa)
    well would it be more exo or endo, once you've got that in your head then no need to worry about remembering which way it goes , I dont know though haha hoping someone will pop up who knows
    lattice dissociation would be more endothermic
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    (Original post by vish.handa)
    well would it be more exo or endo, once you've got that in your head then no need to worry about remembering which way it goes , I dont know though haha hoping someone will pop up who knows
    i remeber my teacher always talking about the size and polarity of atoms/ions when it came to these types of questions but im not too sure how they relate(i doze in class really easily)
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    (Original post by Kikstar)
    Hi! Could someone PLEASE tell me how you know if there will be a further reaction, if given E theta values of electrochemical cells? I'm feverishly trying to look through notes haha


    Posted from TSR Mobile
    Q7(d) in Jan 13 is a good example of this - look at the mark scheme to clarify.

    Essentially one oxidising agent is strong enough to oxidise the reducing agent twice
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    (Original post by GO97)
    anything without an essay is a steal in my eyes haha. lets hope we get the grades we need
    That's one of the only nice things about the paper :P

    Good luck for your exams!
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    (Original post by GO97)
    i remeber my teacher always talking about the size and polarity of atoms/ions when it came to these types of questions but im not too sure how they relate(i doze in class really easily)
    smaller ions increases the lattice enthalpy and so will increased charge
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    (Original post by Hopefulmedic15)
    Q7(d) in Jan 13 is a good example of this - look at the mark scheme to clarify.

    Essentially one oxidising agent is strong enough to oxidise the reducing agent twice
    Thank you so much! I can now sleep in peace haha. Best of luck in your exams


    Posted from TSR Mobile
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    [Al(h20)6]2+ + OH- ===> [Al(OH)4]- + 3h20

    is this equation right for excess oh- being added to aluminium
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    Can someone tell me bond angles for square planar please?
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    (Original post by Anam)
    [Al(h20)6]2+ + OH- ===> [Al(OH)4]- + 3h20

    is this equation right for excess oh- being added to aluminium
    [Al(H2O)6]3+ + 4OH- -> Al(OH)4- + 6H2O
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    (Original post by Anam)
    [Al(h20)6]2+ + OH- ===> [Al(OH)4]- + 3h20

    is this equation right for excess oh- being added to aluminium
    [Al(H2O)]3+ +4OH- ------> [Al(H2O)2(OH)4]- + 4H2O
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    (Original post by Anam)
    [Al(h20)6]2+ + OH- ===> [Al(OH)4]- + 3h20

    is this equation right for excess oh- being added to aluminium
    that doesnt look right to me because youve lost 3 hydrogens from the complex to form 3 water but there is 4OH with your aliminium
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    (Original post by Boundless_x)
    Can someone tell me bond angles for square planar please?
    90
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    (Original post by Anam)
    [Al(h20)6]2+ + OH- ===> [Al(OH)4]- + 3h20

    is this equation right for excess oh- being added to aluminium

    I thought it was [Al(h20)6]3+ + 6OH- [Al(OH)6]3- +6h20
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    (Original post by handiepie)
    I thought it was [Al(h20)6]3+ + 6OH- [Al(OH)6]3- +6h20
    no thats for hexa-aqua Cr3+ in excess oh
 
 
 
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