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    (Original post by a.adi1998)
    i wrote 1200 i didnot write the sign and in the graph i forgot the sign will i lose any mark
    Idk,Maybe you will,Maybe you won't,Firstly it was an enthalpy change question so usually a sign is included but the question WAS about combustion so MAYBE you will gain a mark.

    (Original post by don't cry-craft)
    I feel like many of us messed up the carbonate ion (and therefore the equation) - I mean I did. Don't worry, hopefully the grade boundaries won't be too high. Good luck with your other exams ))
    Thx
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    (Original post by I <3 WORK)
    But the heat loss will make it less exothermic not more exothermic - so it won't be valid?
    You are correct.
    The heat loss was a valid statement because the students who performed the experiment got a value which was higher than the actual value (less exothermic)
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    (Original post by Blazyy)
    You are correct.
    The heat loss was a valid statement because the students who performed the experiment got a value which was higher than the actual value (less exothermic)
    You mean it wasn't valid?
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    (Original post by don't cry-craft)
    I'm not too sure about this. Maybe not as it is enthalpy change of combustion.
    and maybe because its mentioned in the question
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    (Original post by I <3 WORK)
    You mean it wasn't valid?
    What you said was correct. But the statement itself was valid.
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    What did you guys get for the reason why less of F will be produced?
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    (Original post by don't cry-craft)
    What did you guys get for the reason why less of F will be produced?
    I wrote that secondary haloalkanes are more stable
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    (Original post by don't cry-craft)
    What did you guys get for the reason why less of F will be produced?
    According to Markovnikov's rule the hydrogen from hydrogen halide attaches to the carbon atom in double bond that already has more no of hydrogens in the double bond. So 2 iodo hexane is the major product while F was 1 iodo hexane.
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    (Original post by don't cry-craft)
    What did you guys get for the reason why less of F will be produced?
    I don't remember exactly what the question was,But I linked the Major product and the structure of F,The Major product is favoured so more of it is produced.
    My actual answer was something like 'F is not a major product as blah less no. H blah C atom'. I think I could've expanded that.
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    (Original post by Blazyy)
    What you said was correct. But the statement itself was valid.
    Wait I hope I didn't read the question wrong - the original value they gave was much less exothermic than the actual value later on right? So heat loss will will make it less exothermic not more exothermic - which was the actual value, so not valid?
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    (Original post by I <3 WORK)
    Wait I hope I didn't read the question wrong - the original value they gave was much less exothermic than the actual value later on right? So heat loss will will make it less exothermic not more exothermic - which was the actual value, so not valid?
    The value student got was -800 kJ/mol
    While the Data booklet value was -1367.3 kJ/mol
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    I'm really sorry but I've gotten confused xD
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    (Original post by OnTheHorizon)
    I don't remember exactly what the question was,But I linked the Major product and the structure of F,The Major product is favoured so more of it is produced.
    My actual answer was something like 'F is not a major product as blah less no. H blah C atom'. I think I could've expanded that.
    The answer to that was : The intermediate carbocation is a primary carbocation.
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    (Original post by AlonsoAMG)
    I got -418kJ mol-1
    I totally misses the square brackets outside the formula and multiplied 12 with (4.2x400) and then added 117 to it There goes 5 marks
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    (Original post by Ahmed3651998)
    The answer to that was : The intermediate carbocation is a primary carbocation.
    the question was : explain in the terms of intermediate blah blah why it is a minor product?
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    (Original post by ToxicPhantom007)
    The value student got was -800 kJ/mol
    While the Data booklet value was -1367.3 kJ/mol
    Yes exactly so the actual value is more exothermic. And therefore when the temperature change will decrease it is less exothermic and it would make the student's value even less exothermic (so a bigger percentage error). And that's why I said it's not valid.
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    (Original post by notsoclueless)
    I totally misses the square brackets outside the formula and multiplied 12 with (4.2x400) and then added 117 to it There goes 5 marks
    Dw u can do better in unit 1 and 2
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    I got the percentage as 59 % (as it was 58.5 %)
    How many marks was it ?
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    (Original post by Ahmed3651998)
    The answer to that was : The intermediate carbocation is a primary carbocation.
    I thought it was a secondary carbocation?
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    (Original post by I <3 WORK)
    Yes exactly so the actual value is more exothermic. And therefore when the temperature change will decrease it is less exothermic and it would make the student's value even less exothermic (so a bigger percentage error). And that's why I said it's not valid.
    This is really knocking my head off :/
 
 
 
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