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    (Original post by Dave_Beeston)
    Carbon Capture and Storage is the removal of waste carbon dioxide. Decarbonised fuels where hydrocarbons are reacted with water to produce CO2 and H2 are used. CO2 is then siphoned off under ground deep in the sea beds where oil drills used to be, which then pushed up any excess oil. Or CO2 can be "scrubbed". CO2 reacts with Metal Oxides to produce unreactive Metal Carbonates

    If it comes up in a question like "Suggest how scientists are trying to minimise the effect of global warming." then you'll get one mark for mentioning Carbon Capture and Storage, and 2 marks for the examples given above. You can also mention finding a use for carbon dioxide such as fizzy drinks (Yes it actually gets you the mark!) and decaffeinated coffee. Then you'll want to mention the Kyoto agreement in which all of the countries that signed up pledged to reduce carbon emissions by 2012 or pay a carbon tax. You could also say about how scientists are keeping the government informed, educating schools about climate change, and monitoring the effects of global warming. Finally, you should mention that scientists are assessing the impacts of CO2 increasing.

    Hope that helps

    EDIT: As you mentioned the decarbonised fuel equations:

    C4H8 + 8H2O -> 4CO2 + 12H2

    Just as an example I'd remember it incase it comes up!
    thankyouu, what do you mean by "Decarbonised fuels where hydrocarbons are reacted with water to produce CO2 and H2 are used."
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    http://chemnotes.org.uk/f322.html

    this page got some good revision notes
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    how do you work out the enthalpy change of a reaction if you are given bond enthalpies?
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    (Original post by Jubilee~)
    how does the infrared being absorbed by bond contribute to global warming?
    is it because the radiation will be re-emitted as heat & therefore contribute to the global warming?
    The infrared radiation comes from the Sun, where the light reflects off the earth's surface as heat energy/infrared rays. The bonds in molecules in the stratosphere-such as methane, carbon dioxide, water etc.-absorb the infrared radiation as it reflects from the Earth's surface. The bonds vibrate, and prevent the radiation leaving the atmosphere. Hence, the Earth hold the infrared radiation, heats up, and global warming is the result. Hope this helps you...
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    (Original post by Jubilee~)
    how does the infrared being absorbed by bond contribute to global warming?
    is it because the radiation will be re-emitted as heat & therefore contribute to the global warming?
    - each type of bond absorbs infrared of a particular frequency
    - causing the bonds to vibrate more
    - this energy is transferred to other molecules by collisions
    - so increases their kinetic energy
    - so temperature increases
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    (Original post by lolo-x)
    oh dear, fingers crossed for tomorrow then! have you done all the past papers?
    Yeah, I have done all the papers probably at least 5/6 times each plus some of the old spec papers. I have been going through the specification, I really comes down the exam tommorow and how nice the paper. To make things worse I have come down with a cold.
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    (Original post by Contrad!ction.)
    Crap book is crap.

    erm.. a positively charged species that is attracted to a negatively charged species. Or something like that. I'd probably write delta-positive/delta-negative in the exam.

    Define the term isomer.
    An electrophile is an electron pair acceptor attracted to the high electron density of the pi bond on the C=C double bond.
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    honestly think i'm going to fail, my teacher probably wont even let me carry on
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    HELP

    is the yeast in the fermentation of glucose heterogeneous or homogeneous :/ ???

    has been bothering me all day Lol
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    (Original post by naza911)
    Yeah, I have done all the papers probably at least 5/6 times each plus some of the old spec papers. I have been going through the specification, I really comes down the exam tommorow and how nice the paper. To make things worse I have come down with a cold.
    I have had a cold all week, its been awful I can't wait for this week to be over!
    That sounds good, fingers crossed it will be a lovely paper, good luck!
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    (Original post by Pandit Bandit)
    how do you work out the enthalpy change of a reaction if you are given bond enthalpies?
    You should be given the structure of the reacting chemicals if this is the case. You basically work out the enthalpy change caused by all the bonds breaking on the left hand side of the molecules. Then, work out the enthalpy change of forming the bonds on the right hand side, and subtract this figure from the first you worked out. Use the values in the table you should be given, and dont change signs for each of these two calculations. They should be positive, as it requires energy to break bonds. Hope you understand this a bit better now...
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    (Original post by Jim Lee)
    You should be given the structure of the reacting chemicals if this is the case. You basically work out the enthalpy change caused by all the bonds breaking on the left hand side of the molecules. Then, work out the enthalpy change of forming the bonds on the right hand side, and subtract this figure from the first you worked out. Use the values in the table you should be given, and dont change signs for each of these two calculations. They should be positive, as it requires energy to break bonds. Hope you understand this a bit better now...
    Thanks! i was subtracting them the wrong way round
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    can anyone tell me about the mechanisms please? Confusing me so much.

    Like what's the difference between electrophillic/neutrophillic substitution/addition/elimination??

    And how to work it out? Thanks!!
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    (Original post by vasu93)
    http://chemnotes.org.uk/f322.html

    this page got some good revision notes
    Thanks
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    (Original post by Jubilee~)
    thankyouu, what do you mean by "Decarbonised fuels where hydrocarbons are reacted with water to produce CO2 and H2 are used."
    The decarbonised fuel is the H2 produced because that is then used for combustion as it doesn't produce any carbon dioxide The hydrocarbon is mixed with water in the equation I showed above and it produces CO2 and H2 rather than reacting with oxygen itself as a fuel. So the equation I said above isn't the process which gives the energy, it's the burning of the H2!
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    Heyy can someone please check these let me know if ive missed reactions or if any are wrong....

    Cracking...Zeolite catalyst...at 450 deg
    Isomerisation...Zeolite catalyst
    Reforming...Platinum and another metal as the catalysts
    Hydrogenation...Nickle catalyst...at 150 deg
    Hydration...H3PO4 catalyst...at 300 deg...60 atm
    Fermentation...Yeast...at 37 deg
    Dehydration...Conc H2SOR or H3PO4 and reflux
    Haber Process...Iron catalyst...400-500deg ...200 atm
    Radical polymerisation...200deg and high pressures
    Ziegler-Natta...TiCl3 or Al(C2H5)2 at 60 deg
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    (Original post by shuty)
    Heyy can someone please check these let me know if ive missed reactions or if any are wrong....

    Cracking...Zeolite catalyst...at 450 deg
    Isomerisation...Zeolite catalyst
    Reforming...Platinum and another metal as the catalysts
    Hydrogenation...Nickle catalyst...at 150 deg
    Hydration...H3PO4 catalyst...at 300 deg...60 atm
    Fermentation...Yeast...at 37 deg
    Dehydration...Conc H2SOR or H3PO4 and reflux
    Haber Process...Iron catalyst...400-500deg ...200 atm
    Radical polymerisation...200deg and high pressures
    Ziegler-Natta...TiCl3 or Al(C2H5)2 at 60 deg
    Do we even need to know the last one??
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    (Original post by hash007)
    can anyone tell me about the mechanisms please? Confusing me so much.

    Like what's the difference between electrophillic/neutrophillic substitution/addition/elimination??

    And how to work it out? Thanks!!

    Electrophillic addition - HBr/HCl/HI
    -electrophile attracted to the electron rich region/centre/atom where it accepts a pair of electron to form a covalent bond.
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    (Original post by Pandit Bandit)
    Thanks! i was subtracting them the wrong way round
    Here's an easy way to remember it (I don't want this to confuse anyone because it's a different method but it's just the way my chem teacher does it so spoiler):
    Spoiler:
    Show
    the arrows always go downwards!

    -------------Elements------------
    -----------/-------------\-----------
    ----------/---------------\-----------
    ----Reactants-->--Products-----
    ---------\-----------------/----------
    ----------\---------------/-----------
    -----Combustion Products------

    I can't draw the arrow heads on this, but the arrow is always pointing down. I.e. from "reactants" to "combustion products" and from "products" to "combustion products" if you are finding enthalpy change of formation. The arrows go from "elements" to "reactants" and also to "products" for when you're finding the enthalpy change of combustion. Then it's literally like following a vector in maths. If you're finding the enthalpy change of formation you go down the reactants arrow and up the products (easy way of remembering reactants - products). If you're finding the enthalpy change of combustion you go up the reactants and down the products (easy way of remembering -reactants + products).


    Hope that helps!
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    (Original post by lebrondd)
    Do we even need to know the last one??
    Probably
 
 
 
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