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    It was 33.

    Equation was

    N2 + 2O2 -> 2N02

    Enthalpy Change of Formation of N02

    1/2 N2 + 02 -> NO2

    66/2 = 33.

    http://chemistry.about.com/od/thermo...-Formation.htm

    About halfway down, on right hand side column. Formation of NO2 = +33.9
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    (Original post by j_pratt_2003)
    It was 33.

    Equation was

    N2 + 2O2 -> 2N02

    Enthalpy Change of Formation of N02

    1/2 N2 + 02 -> NO2

    66/2 = 33.

    http://chemistry.about.com/od/thermo...-Formation.htm

    About halfway down, on right hand side column. Formation of NO2 = +33.9

    Aha! I knew it!
    All my friends called me silly - "You only had to look at it to see it was 66!". I started doubting myself and convinced myself it didn't show 2NO2.
    I know it was only a one marker, but that's made me happy :L
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    (Original post by king1234)
    what did you get for the equilbruim one about pressure
    I already posted this answer quite a few pages up, let me find it..


    The equilibrium question was asking you why it took shorter time for the reaction to get into a dynamic equilibrium with pressure increase. Basically, this was rate of reaction increasing, more particles per unit volume, more frequent collisions, more successful collisions etc.

    Then it also said why does the composition of the mixture not change with an increase in pressure? This is because increase in pressure favours the side with the least gaseous moles, in the equation both sides had an equal number of gaseous moles (both had 2) so position of equilibrium did not change, there was no NET effect on composition.
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    (Original post by racheatworld)
    I already posted this answer quite a few pages up, let me find it..


    The equilibrium question was asking you why it took shorter time for the reaction to get into a dynamic equilibrium with pressure increase. Basically, this was rate of reaction increasing, more particles per unit volume, more frequent collisions, more successful collisions etc.

    Then it also said why does the composition of the mixture not change with an increase in pressure? This is because increase in pressure favours the side with the least gaseous moles, in the equation both sides had an equal number of gaseous moles (both had 2) so position of equilibrium did not change, there was no NET effect on composition.
    kk thanx lol
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    What did you guys write for the question on how could we deal with the waste of plastics or something? It was before the international co-operation question? :s
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    Hi guys for the reaction of 1-methylcyclohexene with hydrogen, did you draw a straight chain alkene as the formula of 1-methylcyclohexene is C7H12?
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    Any unofficial mark scheme as of yet???
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    (Original post by bradshawm05)
    Hi guys for the reaction of 1-methylcyclohexene with hydrogen, did you draw a straight chain alkene as the formula of 1-methylcyclohexene is C7H12?
    I put methylcyclohexane, as the addition of hydrogen would get rid of the double bond in the cyclic molecule.
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    (Original post by bradshawm05)
    Hi guys for the reaction of 1-methylcyclohexene with hydrogen, did you draw a straight chain alkene as the formula of 1-methylcyclohexene is C7H12?
    All it was that you had to remove the double bond but keep the methyl group on it, i.e. draw methylcyclohexane
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    (Original post by Jim Lee)
    I put methylcyclohexane, as the addition of hydrogen would get rid of the double bond in the cyclic molecule.
    could you draw it out here lol if you dont mind how it would look and how would the other two look when you add hbr
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    (Original post by king1234)
    does anyone think the grade boundaries will be lower for this one i found it harder than june2010 and jan 11 anyone agree lol if not im stuffed wont gte my A
    onda same boat me friend i think grade boundaries should be down defo it was much harder than june 10 and bit harder than jan 11, i may miss my A aswell
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    (Original post by akydon619)
    onda same boat me friend i think grade boundaries should be down defo it was much harder than june 10 and bit harder than jan 11, i may miss my A aswell
    yara i revised for chem a swell inshallah we will get the grade man
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    Does anyone know why for the question:
    which process is not 100% atomeconomy?
    If was the ester and water one and not the cracking one?
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    for the 2-methyl-propan-2-ol i put methylpropan-2-ol .... is this not considered as the same thing as the methyl can only actually be on the second carbon therefore would i still get the mark pleaseeeeee say yes
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    (Original post by Kir4nK)
    for the 2-methyl-propan-2-ol i put methylpropan-2-ol .... is this not considered as the same thing as the methyl can only actually be on the second carbon therefore would i still get the mark pleaseeeeee say yes
    might not i think do you have to put the dashes in i got 2-methyl-propan-2-ol but didnt but the dashes in
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    (Original post by king1234)
    might not i think do you have to put the dashes in i got 2-methyl-propan-2-ol but didnt but the dashes in
    wooooooo i got the same answer as you

    .....again :lolwut:
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    (Original post by Kir4nK)
    for the 2-methyl-propan-2-ol i put methylpropan-2-ol .... is this not considered as the same thing as the methyl can only actually be on the second carbon therefore would i still get the mark pleaseeeeee say yes
    I think you are correct, I put that too because the 2-methyl is not needed as there is no other place that it could be. The '2-' is unnecessary
    Don't worry
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    (Original post by king1234)
    might not i think do you have to put the dashes in i got 2-methyl-propan-2-ol but didnt but the dashes in
    i mean i put all the dashes and all that crap lol but did there need to be a 2 infront of he methyl because from my understanding even f there was no 2 infront of the methyl it still would nt matter because the only carbon the methyl can attach to is the 2nd one otherwise it wouldnt be methylpropan-2-ol ???????
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    (Original post by StrawberryKoi)
    wooooooo i got the same answer as you

    .....again :lolwut:
    erm what did you get for that question a bout the atom aconomy ones
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    (Original post by Nick526)
    I think you are correct, I put that too because the 2-methyl is not needed as there is no other place that it could be. The '2-' is unnecessary
    Don't worry
    oh k tht makes me feel awhole lot better lolll
 
 
 
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