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OCR AS - Chemistry Unit F322 - Chains, energy and resource - REVISION! watch

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    (Original post by shooby_doo)
    Did anyone put a curly arrow on K?
    I was wrong to do that ... the electrons dont go to k do they ....
    Will i lose a mark for taht?
    I think you just had to show OH. Pretty effing sneaky of OCR if we had to put K.
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    would methanol fuel cell not be accepted?
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    (Original post by 786girl)
    please could someone clarify these;

    1. general formula of alcohol, why cant it be CnH2n+2O

    2. international cooperation?

    3. for the hydrolysis question - how many marks was it?

    4. the last question i got the alcohol wrong but i got up to identifying its fragment and molecular formular but i drew it wrong which lead me to name it wrong which lead me to identify X as propyl propanoate! how many marks do u reckon i lost?
    1. i wrote CnH2n+2O and i think we'll get the mark because it is still correct really

    2. i put something like it is important because otherwise there would still be waste being produced blablahblaaa it was a muddled answer, not entirely sure what they were after :/

    3. 10 marks for the hydrolysis question i think

    4. i think you will have lost 1 for naming the alcohol wrong and maybe 1 or 2 for identifying X wrong but not too many as long as you got propanoic acid you will have got a couple marks for working out the empirical formula and identifying the peaks and stuff
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    For the nucleophilic substitution reaction did you have to show both Cl and Br's mechanism or only one? And what if you have shown both?
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    (Original post by 786girl)
    would methanol fuel cell not be accepted?
    didn't it say "apart from fuels and solvents"?
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    (Original post by newreaper19)
    Did anyone else notice that on the last the question the melecular ion for Y was at 47, but there are no alcahols that can be formed with 47m/z. :confused:

    ..............................
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    (Original post by CPN)
    For the nucleophilic substitution reaction did you have to show both Cl and Br's mechanism or only one? And what if you have shown both?
    i showed both to be on the safe side
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    (Original post by thefirstnotlastsamurai)
    I thought the paper started off quite confusing but then got better.

    My answers roughly - don't get disheartened/pissed off if our answers don't match, there's no guarantee I'm even right.

    Respiration formula was standard.
    Why is it endothermic Bond breaking is endothermic, bond breaking is exothermic, one outweighs the other, can't remember which one i put, nor do i have the mental capacity to work it out now.
    Enthalpy question -2793 or something in that region.
    Activation energy minimum energy needed to begin breaking reactant bonds and kick start a reaction.
    Why cant you measure formation directly Activation energy is too high.

    Dynamic system question - collision theory, more particles in same volume, closer together on average, all that jazz.
    Car Exhaust not a closed system
    Compare alkanes and alcohols I just waffled on about one has van der waal forces, the other has hydrogen bonds, hydrogen are stronger than vandewaals. And something about boiling points.
    Name the monomer But-1-ene?

    Ozone mechanism NO + 03 ------> N02 + 02 (1) NO2 + 0 ---------> NO + O2 (2) Overall: O3 + O ------> 2O2


    Use for methanol Feedstock (just wrote that, not sure if i'll get a mark for putting just that)
    Tertiary Alcohol 2-methylpropan-2-ol
    Secondary Butan-2-ol
    Why one dissolves in water Polar OH- group forms hydrogen bonds.
    Complete combustion of methanol CH3OH + 1.5O2 -------> CO2 + 2H20
    Incomplete CH3OH + O2 ------> CO + 2H20

    Cracking Process 5 i think i put?
    Isomer product Process 1?
    One of the answers F
    The other one ahah D&E

    Drawing it First drawing just took the double bond out, next two, drew the methyl group, but then had the bromine next to the methyl group on one picture, then at the other point for the other.

    Shapes Tetrahedral and then trigonal i think?

    Mechanism was nucleophilic substitution, heterolytic, bromoalkane hydrolyzed faster because it was longer, weaker bond enthalpy and more reactive.

    Ester Ethyl Propanoate and all that analysis ****.

    All the green chemistry i just waffled **** loads - CO is poisonous/carcinogenic (i think that's a lie) contributes to acid rain? HCL (acid rain, ground level ozone?) And more stuff - which is probably all lies also.

    Atom economy I thought was better - less waste, more sustainable

    International treaty I invoked gandi and martin luther king as i began preaching about saving the world by reducing polymers.

    That is all i can actually remember - hope any of that helps.
    It's my third time doing it (got 118/150 both times) Keep resitting, your chemistry ability will continually get better.

    Wish all of you luckk.

    Were the only equations that we had to write out, was it just the radical one and the incomplete/complete combusion? I keep on thinking that there was another one to do with NO (Nirtrogen Monoxide), and it's really bugging me?
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    (Original post by CPN)
    For the nucleophilic substitution reaction did you have to show both Cl and Br's mechanism or only one? And what if you have shown both?
    it said something like 'write one equation" and then it just said "the mechanism", it didn't say both. but i went through everything i'd written and tried to work out where you'd get the marks and i think you can just draw one. if you've shown both then thats fine but i think only one was needed i did the bromo one
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    (Original post by Abused Tampon)
    isnt it homolytic fission ??
    Radical Substitution is the only one with homolytic fission, there aren't any radicals in nucleophilic substitution - or as far as i know.

    Your name is epic haha.
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    (Original post by Music22)
    Were the only equations that we had to write out, was it just the radical one and the incomplete/complete combusion? I keep on thinking that there was another one to do with NO (Nirtrogen Monoxide), and it's really bugging me?
    i think there was a question that asked you to explain how NO catalyses the depletion of the ozone layer with the aid of equations?
    you had to do
    O3 + NO --> O2 + NO2
    NO2 + O --> O2 + NO
    overall equation: O3 + O --> 2O2
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    (Original post by Abused Tampon)
    isnt it homolytic fission ??
    nope because it form a positive ion and a negative ion

    homolytic would have formed 2 radicals
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    (Original post by Music22)
    Were the only equations that we had to write out, was it just the radical one and the incomplete/complete combusion? I keep on thinking that there was another one to do with NO (Nirtrogen Monoxide), and it's really bugging me?
    Yeah there was one actually.

    2NO + O2 ------> 2NO2 or something like that?
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    (Original post by lolo-x)
    i think there was a question that asked you to explain how NO catalyses the depletion of the ozone layer with the aid of equations?
    you had to do
    O3 + NO --> O2 + NO2
    NO2 + O --> O2 + NO
    overall equation: O3 + O --> 2O2
    Ahh thanks, so that and the incomplete/complete combustion were the only equations?
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    (Original post by Music22)
    Ahh thanks, so that and the incomplete/complete combustion were the only equations?
    umm... the first question was showing the combustion of glucose i think? something along those lines? can't think of any others though
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    (Original post by lolo-x)
    1. i wrote CnH2n+2O and i think we'll get the mark because it is still correct really

    2. i put something like it is important because otherwise there would still be waste being produced blablahblaaa it was a muddled answer, not entirely sure what they were after :/

    3. 10 marks for the hydrolysis question i think

    4. i think you will have lost 1 for naming the alcohol wrong and maybe 1 or 2 for identifying X wrong but not too many as long as you got propanoic acid you will have got a couple marks for working out the empirical formula and identifying the peaks and stuff
    thanks yeh hopefully we'll get the formula!
    also are you the one who posted the notes on unit 2 in a world file? they were a life saver! thanx!
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    (Original post by lolo-x)
    umm... the first question was showing the combustion of glucose i think? something along those lines? can't think of any others though
    ahh ok thanks!
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    (Original post by thefirstnotlastsamurai)
    Yeah there was one actually.

    2NO + O2 ------> 2NO2 or something like that?
    I remember something like that, but I can't quite remember it exactly... thanks though, hopefully I'm not going insane aha!
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    (Original post by shooby_doo)
    Dam, it was really stupid of me to put alcoholic drinks for the uses of methanol question! LOL Even though i sat there, fully aware that ethanol is the only really used alcohol for drinks ... i decided to stick with it ....
    I feel so stupid, especially as perfume was quite an obvious one ....
    SAME SAME SAME I knew perfectly well it was ethanol, I was in denial haha
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    why is everyone panaking over a one mark question
    on another use of methanol! ..
    there was 2 10 marks
    and stupid 3 mark or 4 mark questions about
    wtf to do with co2 ..and what countries should do ???
    that was annoying! coz i didnt even no what they would mark right/wrong
 
 
 
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