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    For the methylpropene multiple choice - the longest chain was 4 carbons long so it was a stereo isomer of butene- i think E -isomer?
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    (Original post by uz2y)
    Could you say that the alcohol could have evaporated on the way to the apparatus? (after you weighed it for the first time to get the initial weight)
    yeah thats another reason but im not sure if they accept it though dont take my word for it
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    Name:  1.png
Views: 199
Size:  5.8 KBFor the double alcohol one I got the two answers below
    Theyre bad diagrams but is that correct?
    For the equation it was 3 [O] and 2H20 right?
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    For the first part of Q2 when you use q=mcT to work out the change in enthalpy for methanol, what was the answer? I remember getting 0.005 something anyone confirm or deny?
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    (Original post by creative_lad28)
    For the first part of Q2 when you use q=mcT to work out the change in enthalpy for methanol, what was the answer? I remember getting 0.005 something anyone confirm or deny?
    The overall answer was -307kj mol -1
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    (Original post by gcsekid)
    More answers
    1) Students value inaccurate? Copper calorimeter absorbs heat
    2) Catalyst: Lowerst Activation energy by providing alternative pathway for reaction
    3)Mass spectrometry can't be used: Rounded figures are the same, and not accurate ro enough decimal places to distinguish
    Multiple Choice:
    C: CH3CHO
    D: Nucelophilic Substitution
    B: Mechanism picture
    D: yield 86%
    A: Sulfur dioxide removed in gas station
    D: Repeating Polymer Methypropene
    D: Maxwell Boltzmann Curve picture
    A: Hexane question
    B: Cn2n-2 formula
    C: A+3B->C+2D gives 18 moles
    C: Increase Temperature (yield of h2 an Kc)
    B: 1064 missing enthalpy
    Thank you!

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    ye thats wrong, i am guessing you went wrong by using the mass wrong in q=mc(d)t - the mass was the mass of water (100g) then 38 temp with 4.18 when you have that value you divide by a thousand to get kJ mol-1. Then you get the moles by taking away the original mass of the substance and after combustion and divide that by the Mr (Mr use your periodic table). Then you use q/n and plug in the values and then you change the sign if needed depending on if its exothermic or endothermic.
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    (Original post by Enderbat1999)
    no it said dont meantion heat transfor to equipment
    I said the value in the data booklet probably included many experiments and taken and average but this is only one individual experiment
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    (Original post by gcsekid)
    More answers
    1) Students value inaccurate? Copper calorimeter absorbs heat
    2) Catalyst: Lowerst Activation energy by providing alternative pathway for reaction
    3)Mass spectrometry can't be used: Rounded figures are the same, and not accurate ro enough decimal places to distinguish
    Multiple Choice:
    C: CH3CHO
    D: Nucelophilic Substitution
    B: Mechanism picture
    D: yield 86%
    A: Sulfur dioxide removed in gas station
    D: Repeating Polymer Methypropene
    D: Maxwell Boltzmann Curve picture
    A: Hexane question
    B: Cn2n-2 formula
    C: A+3B->C+2D gives 18 moles
    C: Increase Temperature (yield of h2 an Kc)
    B: 1064 missing enthalpy
    it specifically said to not write about heat loss
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    (Original post by britishtf2)
    "My multichoice were: CDDABBDCABCDCBD. I do not know if they are correct, however. GJ on the mark scheme "

    What I said. That one is likely not the only one which is wrong, but it was just a guide ^
    Sorry about the misunderstanding, I reworded the sentence
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    How does NO and CO react?2NO + CO ----> N2 + CO2

    Shouldn't this be 2no + 2co > n2 + 2ci2? The oxygens don't balance in your equation ^^
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    (Original post by Splaffie)
    it specifically said to not write about heat loss
    It specifically said not to write about heat loss to the ATMOSPHERE.
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    (Original post by river222)
    Name:  1.png
Views: 199
Size:  5.8 KBFor the double alcohol one I got the two answers below
    Theyre bad diagrams but is that correct?
    For the equation it was 3 [O] and 2H20 right?
    You got the equation right I believe, but the the displayed formula for the potassium dichromate not in excess was a ketone and Aldehyde.
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    (Original post by liziepie)
    How does NO and CO react?2NO + CO ----> N2 + CO2

    Shouldn't this be 2no + 2co > n2 + 2ci2? The oxygens don't balance in your equation ^^
    Oops. I really thought I changed it already. I must have forgotten. I'll change it now. Thank you!
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    (Original post by DaVinciGirl)
    You got the equation right I believe, but the the displayed formula for the potassium dichromate not in excess was a ketone and Aldehyde.
    But isn't the secondary alcohol when it forms a ketone must be under reflux? I'm pretty sure it said it wasn't under reflux and only used a little oxidising agent so it wouldn't be enough to form it? So it'd be just an aldehyde?
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    (Original post by river222)
    But isn't the secondary alcohol when it forms a ketone must be under reflux? I'm pretty sure it said it wasn't under reflux and only used a little oxidising agent so it wouldn't be enough to form it? So it'd be just an aldehyde?
    I really can't remember the actual wording. Sorry! I thought it was still in reflux. If anyone can help with this that would be great.
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    Why does CO or CO2 has higher absorption of Infrared radiation?
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    (Original post by Jason.CCY)
    Why does CO or CO2 has higher absorption of Infrared radiation?
    I wrote they have a high bond enthalpy.
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    Just asked my physics and chem teacher just now and it's 1.31% for the uncertainty!
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    (Original post by DaVinciGirl)
    It specifically said not to write about heat loss to the ATMOSPHERE.
    Wouldn't heat loss to apparatus still count as heat loss to enviroment? I thought it might be because data book value uses mean bond enthalpy, but not sure for that one ...
 
 
 
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