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    for the shape I got the first one as tetrahedral but forgot the second one, guessed pyramidal, guess thats wrong ;L
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    (Original post by EternalDoom)
    Hmmmmmmmmmmms, what did people put for why enthalpy change of formation was hard to calculate exactly? I said it was hard to perform under standard conditions


    Only questions that were hard were the little 2-markers that havent come up in past papers
    I put that other compounds might've been formed by the reactants. :dontknow:
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    (Original post by EternalDoom)
    Hmmmmmmmmmmms, what did people put for why enthalpy change of formation was hard to calculate exactly? I said it was hard to perform under standard conditions


    Only questions that were hard were the little 2-markers that havent come up in past papers
    Other products produced, slow rate, high activation energy, is what I put, as it didn't specify that it wanted only one answer, which they usually do with, "Give one reason why etc..."
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    Anyone get plus 1279?
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    (Original post by Abused Tampon)
    what did people get for the question about the enthalpy change of amonia? N2 + H2 ----> NH3
    with Delta H = - or +66
    and what was the answer?
    Half it to +33 i think
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    I wonder if this thread can overtake the biology one
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    (Original post by Abused Tampon)
    what did people get for the question about the enthalpy change of amonia? N2 + H2 ----> NH3
    with Delta H = - or +66
    and what was the answer?
    there was no ammonia question....


    u mean nitrogen monoxide to make nitrogen dioxide right?


    NO + 02 ---> NO2 + O


    and then nitrogen monoxide breaking down ozone:

    NO + O3 --- NO2 + O2
    NO2 + O ---- NO + O2
    O3 + O ---- 2O2
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    (Original post by EternalDoom)
    Hmmmmmmmmmmms, what did people put for why enthalpy change of formation was hard to calculate exactly? I said it was hard to perform under standard conditions


    Only questions that were hard were the little 2-markers that havent come up in past papers
    i put the energy is contained within the bonds themselves making it impossible to work out exactly, only the change to the surrounding breaking these bonds causes
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    (Original post by Abused Tampon)
    what did people get for the question about the enthalpy change of amonia? N2 + H2 ----> NH3
    with Delta H = - or +66
    and what was the answer?
    +33

    You had to divide by 2 to per enthalpy change per mole
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    PS Helper
    (Original post by ChessMister)
    No, he means 2 methylpropan-2-ol
    You don't have to put a 2 in front of the methyl on methyl propan-2-ol, because it only has 3 carbons the methyl can only go in one place (on the second carbon), otherwise if it was put on the first carbon the longest carbon chain would be 4, so it would turn into butan-2-ol.
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    I FAILED THE LAST QUESTION SO BADLY :mad:

    BTW I HOPE ALCOHOL WORKS AS THE USES OF METHANOL :confused:
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    (Original post by EternalDoom)
    there was no ammonia question....


    u mean nitrogen monoxide to make nitrogen dioxide right?


    NO + 02 ---> NO2 + O


    and then nitrogen monoxide breaking down ozone:

    NO + O3 --- NO2 + O2
    NO2 + O ---- NO + O2
    O3 + O ---- 2O2
    Samesies! Boom!
    Also, around -1270 can't remember exact. Ethyl Propanoate. Methylated spirits (probably wrong).

    THe only question I was really unsure about was the 'how is IR spec used to analyse NOx in the atomosphere and other pollutants ect'?/
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    (Original post by viksta1000)
    +33

    You had to divide by 2 to per enthalpy change per mole
    Ahhhh crap lost a stupid mark there....
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    (Original post by viksta1000)
    +33

    You had to divide by 2 to per enthalpy change per mole
    :eek:

    Great.........there goes another mark xD

    I thought it was too easy, just transferring a number?! :mad:
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    (Original post by racheatworld)
    You don't have to put a 2 in front of the methyl on methyl propan-2-ol, because it only has 3 carbons the methyl can only go in one place (on the second carbon), otherwise if it was put on the first carbon the longest carbon chain would be 4, so it would turn into butan-2-ol.
    ahh
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    Isn't the enthalpy change of formation difficult to work out directly because elements have no enthalpy change of formation themself?

    God, I shouldn't read these threads, it's so self-destructive. You always see where you misread a question or rushed an answer or made a stupid error!
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    (Original post by Awesomesauce)
    Samesies! Boom!
    Also, around -1270 can't remember exact. Ethyl Propanoate. Methylated spirits (probably wrong).

    THe only question I was really unsure about was the 'how is IR spec used to analyse NOx in the atomosphere and other pollutants ect'?/
    I wrote it is used to find what functional groups are present in the pollutants, as the covalent bonds vibrate when a functional group is present.....


    The small 2 markers really annoyed me
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    ethylpropanoate is what i got for the ester :/ hope thats right

    and for the enthalpy change would i loose the mark for putting +66 ?? or did it really have to be 33 ((((
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    The other use of methanol methylated spirits?
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    For the last part will there be marks for the fragment ions that I found? even though i got the propanoic acid wrong
 
 
 
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