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    The complete combustion of 0.0117mol of X produces 2.00x10^-3 m^3 of carbon dioxide gas, measured at 24.0 degrees and 101kPa.
    Determine the molecular formula of X.

    I'm really not sure how to tackle this question.

    Thanks
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    Your question is far too vague. Please post the full question (with images if possible)
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    Name:  image.jpg
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Size:  505.8 KB Haha I know, that's literally all it says though!
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    (Original post by Farmerjj)
    Name:  image.jpg
Views: 511
Size:  505.8 KB Haha I know, that's literally all it says though!
    Show alkane X! That is crucial to the question!
    Don't worry, some questions, especially ocr require you to look back at the previous information given haha.
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    (Original post by Farmerjj)
    Name:  image.jpg
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Size:  505.8 KB Haha I know, that's literally all it says though!
    It's heptane.

    Use PV = nRT for mol of CO2 produced and compare to mole of X burned
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    (Original post by nwmyname)
    Show alkane X! That is crucial to the question!
    Don't worry, some questions, especially ocr require you to look back at the previous information given haha.
    Oh sorry forgot to put that top bit. 😊
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    (Original post by TeachChemistry)
    It's heptane.

    Use PV = nRT for mol of CO2 produced and compare to mole of X burned
    Alright I'll try that cheers
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    (Original post by TeachChemistry)
    It's heptane.

    Use PV = nRT for mol of CO2 produced and compare to mole of X burned
    I got 0.012 for the moles but how the heck did you get heptane from that?
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    (Original post by Farmerjj)
    I got 0.012 for the moles but how the heck did you get heptane from that?
    Post a picture of your working please.
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    (Original post by TeachChemistry)
    Post a picture of your working please.
    where is this question so I can find it online? is it a specimen paper?
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    (Original post by TeachChemistry)
    Post a picture of your working please.
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    (Original post by nwmyname)
    where is this question so I can find it online? is it a specimen paper?
    It's the new OCR A depth in chemistry but I don't think this ones online
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    (Original post by Farmerjj)
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    You have not rearranged the equation properly AND you have not used the correct value for the volume.
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    (Original post by TeachChemistry)
    You have not rearranged the equation properly AND you have not used the correct value for the volume.
    Sorry here ya go
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    (Original post by Farmerjj)
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    Sorry here ya go
    Now look at the ratio of the number of moles you just calculated and the number of moles given for X in the question.
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    (Original post by TeachChemistry)
    Now look at the ratio of the number of moles you just calculated and the number of moles given for X in the question.
    Oh I get it now man cheers 😄
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    There is a new paper?! What is this?! TeachChemistry it would be the biggest favour in the world if you could put it up online please here on this post!
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    (Original post by Farmerjj)
    Oh I get it now man cheers 😄
    +1 and follow from me for an excellent question.
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    (Original post by nwmyname)
    There is a new paper?! What is this?! TeachChemistry it would be the biggest favour in the world if you could put it up online please here on this post!
    No idea. I'm not the OP.
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    (Original post by Farmerjj)
    The complete combustion of 0.0117mol of X produces 2.00x10^-3 m^3 of carbon dioxide gas, measured at 24.0 degrees and 101kPa.Determine the molecular formula of X.
    I'm really not sure how to tackle this question.
    Thanks
    good revision website www.technocratnotes.com

    and good revision apphttps://play.google.com/store/apps/d...s.app&hl=en_GB

    can you add this to your originalpost please so that any new ppl to the thread see this. thanks
 
 
 
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