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    (Original post by thecdon)
    SEE TOLD YOU THAT QUESTION WAS ONLY WORTH A MARK.....WERE YOU ONE OF THE HATERS THAT WAS DISAGREEING WITH ME??!? YOURE ALL BIATCHES
    ....???ok
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    Personally, i thought both f321 and f322 were decently written papers, maybe apart from the one 1 mark question on atomic radius in f321. Any one else find it alright?
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    (Original post by .captainsarah)
    I got propan-2-ol and propanone in that question - I think pentanol would have had too high a RMM.
    Pretty sure it wasn't a carboxylic acid as there wasn't a dip for the O-H, couldn't have been an aldehyde as was under reflux. At least that's what I'm hoping! The peak that might have been a C-O could be just one of those wierd ones that appear in the fingerprint region

    I got confused on the question with the bromine radicals and methane - when it said that a small amount of ethane may form - ended up babbling on extra paper before I actually got anywhere.
    It was propan-2-one, im sure most people just looked at the chemical tests for secondary alcohols to figure that 1 out.
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    (Original post by JordanCarroll)
    but you did realise in the end that ethane can be formed from .CH3 radicals in the termination phase ?
    Yep, and that the .CH3 radicals are formed by propagation. I basically word-vomitted everything I knew about radicals on the extra paper along with equations for them all :p:
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    (Original post by HotCoco.)
    Catalytic converters convert CO to CO2. [NO2 + 2CO --> 2CO2 + N2] So you are not reducing CO2 emmissions but increasing them! The point of catalytic converters is to get rid of the toxic CO in the atmosphere that is harmful to our health. The disadvantage is that the converters produce less 'harmful' CO2.
    The question was actually asking about how chemists were reducing the greenhouse gas' emissions. It didn't specify CO2, but Catalytic converters convert CO and volatile organic compounds into carbobon dioxide, which has a greenhouse factor meaning it doesn't absorb a smuch infrared radiation and emit it as heat.
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    (Original post by AnthonyShock)
    The question was actually asking about how chemists were reducing the greenhouse gas' emissions. It didn't specify CO2, but Catalytic converters convert CO and volatile organic compounds into carbobon dioxide, which has a greenhouse factor meaning it doesn't absorb a smuch infrared radiation and emit it as heat.
    So would I be credited with some marks if I only wrote about the Catalytic Converters?? Because I forgot about the CCS stuff until after I handed in my paper
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    (Original post by .captainsarah)
    Yep, and that the .CH3 radicals are formed by propagation. I basically word-vomitted everything I knew about radicals on the extra paper along with equations for them all :p:
    haha! good plan
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    (Original post by Haz Shah)
    So would I be credited with some marks if I only wrote about the Catalytic Converters?? Because I forgot about the CCS stuff until after I handed in my paper
    Well depending on how well you have explained catalytic converters, e.g equations you can get a maxiumum of 2 marks. Having looked at an old mark scheme, theres marks for things like " educating the public about the effects of global warming".
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    (Original post by JustDan)
    It was propan-2-one, im sure most people just looked at the chemical tests for secondary alcohols to figure that 1 out.
    It's pointless, and slightly incorrect, to call it "propan-2-one" because you can only get one ketone when the carbon-chain length has 3 carbons.
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    (Original post by Noble.)
    It's pointless, and slightly incorrect, to call it "propan-2-one" because you can only get one ketone when the carbon-chain length has 3 carbons.
    you would still get the mark.its an AS paper after all.
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    Well its more to show the examiner you know which bond has been oxidised, either is acceptable.
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    I made one very stupid recurring mistake in the exam though, I said methane had the molecular formula
    CH3, rather than CH4, for some reason. Do you think they will mark me down heavily (I used that error constantly)?

    And also, did you have to mention that it was propanone, even though I said E/F(?) WAS PROPAN-2-OL; and I also wrote the equation correectly.
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    (Original post by Summerdays)
    I made one very stupid recurring mistake in the exam though, I said methane had the molecular formula
    CH3, rather than CH4, for some reason. Do you think they will mark me down heavily (I used that error constantly)?

    And also, did you have to mention that it was propanone, even though I said E/F(?) WAS PROPAN-2-OL; and I also wrote the equation correectly.
    I'm not sure if OCR will just knock off 1 mark from the whole paper, for not realising methane is CH4, or whether they'll take a mark off every time you've made the error. I know some boards will only penalise you for something like that once throughout the paper.

    The question did state to either name or draw the structures of both E and F. So if you didn't name it was propanone, or draw the structure, you would lose a mark.
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    (Original post by JustDan)
    Well depending on how well you have explained catalytic converters, e.g equations you can get a maxiumum of 2 marks. Having looked at an old mark scheme, theres marks for things like " educating the public about the effects of global warming".
    Ah, my equation was slightly mucked up .. Not balanced properly.. but I said "Reactants such as CO and NO adsorb onto the metal atoms on the surface of the catalyst. Bonds are weakened or broken, and new Bonds are formed, giving CO2 and N2, which are then desorbed from the catalyst.."
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    the alcohol question was worth 7 marks, does anyone have a clue to what u had to write to get all 7. I wrote the compound was propan-2-ol and compound propan-2-one along with eqaution and the absorption wavenumbers from infrared spectrum. Would that get me 7 marks or I have I missed anything?, also does anyone know whether u had to include state symbols in the oxidation equation, because I think I forgot.... D:<
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    (Original post by Noble.)
    I'm not sure if OCR will just knock off 1 mark from the whole paper, for not realising methane is CH4, or whether they'll take a mark off every time you've made the error. I know some boards will only penalise you for something like that once throughout the paper.

    The question did state to either name or draw the structures of both E and F. So if you didn't name it was propanone, or draw the structure, you would lose a mark.
    Fair enough. BTW, how well do you think you did in that whole paper?
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    (Original post by Summerdays)
    Fair enough. BTW, hoe well do you think you did in that whole paper?
    Well, I'm hoping for at least 90%. I'm pretty confident I got 90%, since after going through the paper with my chemistry teacher couldn't find a single question I answered incorrectly.
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    (Original post by Anti-Derivative)
    the alcohol question was worth 7 marks, does anyone have a clue to what u had to write to get all 7. I wrote the compound was propan-2-ol and compound propan-2-one along with eqaution and the absorption wavenumbers from infrared spectrum. Would that get me 7 marks or I have I missed anything?, also does anyone know whether u had to include state symbols in the oxidation equation, because I think I forgot.... D:<
    Saying that the molecular ion peak was 60.
    Identifying from the spectrum that there was C=O absorption, but no O-H absorption you'd expect from a carboxylic acid.
    Realising that it was refluxed, therefore complete oxidation was achieved. From this you can deduce that the product F has to be either a carboxylic acid (complete oxidation of a primary alcohol) or a ketone (complete oxidation of a secondary alcohol). Considering you were able to discount a carboxylic acid as the product, you can deduce that the product F must be a ketone. Hence, E, must be a secondary alcohol. Using the molecular ion peak, it's fairly straight-forward to work out that E is propan-2-ol and F is propanone. Putting the equation for the oxidation:

    C3H8O + [O] ---> C3H6O + H2O

    All of that are probably the criteria for the full 7 marks, purely because questions like that generally don't have 8/9 marking points for a maximum of 7 marks.
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    I found the whole paper to be good. I made some VERY SILLY mistakes. in some parts. Also, what did you put for the very first question and the question?
    And also the question about comparing the two methods of making H2O2, would it be valid to say that stage two of the second method and the method used in stage on, are both substitution reactions?
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    (Original post by Summerdays)
    I found the whole paper to be good. I made some VERY SILLY mistakes. in some parts. Also, what did you put for the very first question and the question?
    And also the question about comparing the two methods of making H2O2, would it be valid to say that stage two of the second method and the method used in stage on, are both substitution reactions?
    Saying they were substitution reactions may be correct, but it's assuming the mechanism the catalyst plays. I think the main points of that question comparing the methods of making H2O2 were the following:

    - The substance used was a catalyst, as it was regenerated at the end.
    - The atom economy of the second method is 100%, compared to the 12.7% of the first method.
    - Less waste is produced (it's also toxic waste, as it stated on the previous question about the disposing of harmful barium compounds).
    - Perhaps something about the catalyst lowering activation energy.

    I'm not sure which other questions you're referring to.
 
 
 
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