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    methanol fuel cell
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    (Original post by Nkhan)
    formation question was -1239
    I got -10 something something...

    You definitely right?
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    I wrote feedstock for cracking
    Better than my answer!...I put anti-freeze :laugh:
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    Anyone doing OCR physics in a couple of weeks?
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    (Original post by timkench)
    whats better, high percentage yield or atom economy?
    I put atom economy.

    (Original post by Joseppea)
    .................hydrolysis is nucleophilic substitution right? O_O
    Yep.
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    (Original post by Joseppea)
    .................hydrolysis is nucleophilic substitution right? O_O
    yes, and mention heterolytic fission!
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    I just put that methanol was used as starting material to create new chemical substances :/
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    You could probably state either as long as you explained yourself well. It just said explain your answer so neither is incorrect and the marks would be for explaining your choice.
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    (Original post by timkench)
    whats better, high percentage yield or atom economy?
    I don't think it will matter in terms of marks because it said in your opinion.

    I put percentage yield, as this measures the efficiency of converting reactants into products and for ethanol production in industry a high conversion of reactants into products is more important for a good yield. Also, I put with fermentation the reaction will always produce CO2, so the atom economy will never be 100%
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    I hate these threads but I can't keep myself out

    What did yall get for the ester?
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    for the hess cycle were the arrows pointing DOWN or UP? it said find formation but it has combustion values helpp
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    (Original post by 786girl)
    methanol fuel cell
    thanks for writing in really big letters.
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    (Original post by 786girl)
    methanol fuel cell
    The question said other than a fuel?

    Plus that isn't on the spec.
    The spec for uses of alcohols is:
    Alcohol drinks (usually from fermentation though)
    Fuels
    Solvents (eg: methylated spirits)
    Feedstock for the production of other organic chemicals

    So except fuel and solvents I put, feedstock.
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    (Original post by ChessMister)
    I hate these threads but I can't keep myself out

    What did yall get for the ester?
    Ethyl propanoate is the correct answer.
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    (Original post by 786girl)
    for the hess cycle were the arrows pointing DOWN or UP? it said find formation but it has combustion values helpp
    I put them pointing down as our chemistry teacher always said

    "For combustion Hess' Law Triangle the products

    BURN IN HELL!" :eek::eek:

    That was echoing in my head the whole time

    ............so pointing down. xD
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    (Original post by nereik6794)
    Wrong
    i got -1279
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    I got positive 1000 something because the arrows had to point down on hess' cycle cause the values given were for enthalpy change of combustion.
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    (Original post by 786girl)
    for the hess cycle were the arrows pointing DOWN or UP? it said find formation but it has combustion values helpp
    I don't think you had to draw Hess's cycle just get the enthalpy change right.
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    For other uses of methanol I put as a cleaning agent, LOL.

    I put that I think percentage yield is more important, because the if the percentage yield is low, that is matter that is physically lost. If the atom economy is low, then you just have to find a use for the waste products and you can make it 100%, but I dunno, hated that paper, a compilation of my very worst topics.
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    (Original post by racheatworld)
    The question said other than a fuel?

    Plus that isn't on the spec.
    The spec for uses of alcohols is:
    Alcohol drinks (usually from fermentation though)
    Fuels
    Solvents (eg: methylated spirits)
    Feedstock for the production of other organic chemicals

    So except fuel and solvents I put, feedstock.
    You can't use Methanol in alcoholic drinks. Otherwise you would be unable to find your way to the toilet in the morning to 'whitey' due to being blind.
 
 
 
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