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    (Original post by Presidential)
    Lol it was 2 its asking for 2 different things.
    I want to make a bet (if the mods allow) about this. sth to do with tsr and not money.
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    (Original post by Summerdays)
    I said that the aircraft provided enough energy to break the tripple bond in N2. Would that count?

    Also, could my above question be answered?
    erm you really only need to talk about triple bonds in N2 when talking about iron acting as a catalyst in the haber process. You could still get the mark because what your saying is pefectly right but it depends on the guy marking your paper.
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    (Original post by nameless_one)
    what did you guys put for
    explain why reactions are sometimes exothermic
    Was that the question which said "use your knowledge of bond breaking/bond forming".

    I 'defined' an exothermic reaction, heat energy is transferred from the reaction mixture to the surroundings. Bond breaking is endothermic, bond forming is exothermic. If the reaction, overall, is exothermic, more energy must be released upon bond formation than the input of energy required to break the bonds.
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    What did you guys put for the 5 marker about greenhouse gases?
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    (Original post by Noble.)
    Was that the question which said "use your knowledge of bond breaking/bond forming".

    I 'defined' an exothermic reaction, heat energy is transferred from the reaction mixture to the surroundings. Bond breaking is endothermic, bond forming is exothermic. If the reaction, overall, is exothermic, more energy must be released upon bond formation than the input of energy required to break the bonds.
    Pefect answer! This is what I wanted to put down lol. Iprobs got 1/2 for that.
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    (Original post by Presidential)
    erm you really only need to talk about triple bonds in N2 when talking about iron acting as a catalyst in the haber process. You could still get the mark because what your saying is pefectly right but it depends on the guy marking your paper.
    Hmm... Ok. And also Alkenes are definitely not used to get rid of HCls?
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    (Original post by Noble.)
    Was that the question which said "use your knowledge of bond breaking/bond forming".

    I 'defined' an exothermic reaction, heat energy is transferred from the reaction mixture to the surroundings. Bond breaking is endothermic, bond forming is exothermic. If the reaction, overall, is exothermic, more energy must be released upon bond formation than the input of energy required to break the bonds.
    ahh do you remember how many marks it was?
    i accidentally did it the wrong way around...
    i put that bond breaking is endothermic
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    (Original post by Summerdays)
    What did you guys put for the 5 marker about greenhouse gases?
    Carbon-capture and storage. React CO2 with metal oxides to produce metal carbonates. Use of bio-fuels as they are carbon-neutral, the CO2 released upon combustion is the same amount the plant took out of the atmosphere during growth. I said Chemists design catalysts that enable plants to reduce pressures/temperatures, so less energy is required for the reaction to take place, therefore, less CO2 emitted.
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    (Original post by nameless_one)
    ahh do you remember how many marks it was?
    i accidentally did it the wrong way around...
    i put that bond breaking is endothermic
    I'm not sure, it was definitely 2 or 3.
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    (Original post by Summerdays)
    What did you guys put for the 5 marker about greenhouse gases?
    CCS
    Decarbonised fuel
    Supercritical CO2

    and then I went into more depth i suppose. No idea where the extra 2 marks went.
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    (Original post by Summerdays)
    Hmm... Ok. And also Alkenes are definitely not used to get rid of HCls?
    Gas scrubbers are used, which is an alkali. I imagine you'd get the mark for stating 'alkali' or KOH/NaOH.
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    (Original post by Noble.)
    Carbon-capture and storage. React CO2 with metal oxides to produce metal carbonates. Use of bio-fuels as they are carbon-neutral, the CO2 released upon combustion is the same amount the plant took out of the atmosphere during growth. I said Chemists design catalysts that enable plants to reduce pressures/temperatures, so less energy is required for the reaction to take place, therefore, less CO2 emitted.
    I mentioned your first three points. I also mentioned catalytic converters in car getting rid of oxides of nitrogen. I also mentioned that CFCs are being replaced with less dangerous HCFCs.

    For the exothermic reaction I said: Energy is used break the bonds and energy is released when the new bonds are made. The total enthalpy change is exothermic. Do you think I will get the marks?
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    (Original post by Noble.)
    I'm not sure, it was definitely 2 or 3.
    hmmm
    okay my dream of 85/90% has just epically failed
    i lost about 2marks on calculations
    must hav lost 2on the 5marker green question
    another 5somewhere else
    ah alllloooooow :mad:
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    Has anyone got the paper yet?
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    (Original post by FoOtYdUdE)
    Tbh, secondary alcohol oxidise to ketones so that's a really stupid error. Gawwwwwd. :p:
    But if u picked a primary alcohol it oxides 2 form a carboxylic acid i think will hav 2 wait 4 da results/ MS
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    (Original post by Summerdays)
    I mentioned your first three points. I also mentioned catalytic converters in car getting rid of oxides of nitrogen. I also mentioned that CFCs are being replaced with less dangerous HCFCs.

    For the exothermic reaction I said: Energy is used break the bonds and energy is released when the new bonds are made. The total enthalpy change is exothermic. Do you think I will get the marks?
    I was going to mention both of those points, but decided not to. Firstly because, the reaction that takes place on a catalytic converter:

    2CO + 2NO --> 2CO2 + N2

    It produces a greenhouse gas, CO2.

    I didn't mention CFCs because, while they are greenhouse gases, the whole focus of OCR AS Chemistry, in regards to CFCs, is Ozone depletion. The reason CFCs are no longer used has very little to do with it being a greenhouse gas.
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    (Original post by xxsaraxx7)
    But if u picked a primary alcohol it oxides 2 form a carboxylic acid i think will hav 2 wait 4 da results/ MS
    The spectrum clearly showed the product couldn't possibly be a carboxylic acid.
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    ^They are still considered a greenhouse gas, because ozone depletion is also responsible for global warming, which is in scarce concentration. I did mention the fact that CO2 being released, but I mentioned that oxides of nitrogen affect ozone more adversely (or something along that line)
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    i want someone to post the paper up!
    and the mark scheme!
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    ¬_¬ lol mods changed my thread title.
 
 
 
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