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    Can anyone help me with this? Thanks and much appreciated, in advance!
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    (Original post by nivvy21)
    Can anyone help me with this? Thanks and much appreciated, in advance!
    300/100000= 0.0030%
    380/100000=0.0038%
    The difference between the two is 0.0008
    But the ms says 0.008 I don't get it tbh either
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    (Original post by Whostolemycookie)
    300/100000= 0.0030%
    380/100000=0.0038%
    The difference between the two is 0.0008
    But the ms says 0.008 I don't get it tbh either
    You divided by 100,000 instead of 10,000


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    (Original post by nivvy21)
    Can anyone help me with this? Thanks and much appreciated, in advance!
    The difference is 80ppm (380 - 300).

    Convert 80ppm to a percentage and that's your answer.
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    Gah, a few hours until the exam >.<
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    what other colour changes do we need to know, apart from the bromine water?
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    (Original post by super121)
    You divided by 100,000 instead of 10,000


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    That was it! I was wondering why I was getting it wrong :rolleyes:
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    (Original post by tasniaa)
    what other colour changes do we need to know, apart from the bromine water?
    When oxidation happens, the aldehyde converts to carboxylic acid and the colour change is orange to green
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    (Original post by Whostolemycookie)
    When oxidation happens, the aldehyde converts to carboxylic acid and the colour change is orange to green
    thank you
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    omg guys do the specimen paper- I swear I thought had done it before because one 1 questions from that pop up in a few papers
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    (Original post by King Hotpie)
    Oh good now I just have to remember it for the next few hours :rolleyes:

    Does anyone know where I could find the January 2013 mark scheme?
    Jan MS.pdf
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    (Original post by Whostolemycookie)
    When oxidation happens, the aldehyde converts to carboxylic acid and the colour change is orange to green
    can you oxidise a ketone?
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    (Original post by nivvy21)
    Can anyone help me with this? Thanks and much appreciated, in advance!
    it's (380 - 300) / 300 ( X100) like you wrote
    or did you want an explanation as to why you do that ?
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    (Original post by madrevision)
    omg guys do the specimen paper- I swear I thought had done it before because one 1 questions from that pop up in a few papers
    good idea xD

    is there a markscheme?
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    (Original post by Whostolemycookie)
    300/100000= 0.0030%
    380/100000=0.0038%
    The difference between the two is 0.0008
    But the ms says 0.008 I don't get it tbh either

    (Original post by super121)
    You divided by 100,000 instead of 10,000


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    (Original post by usycool1)
    The difference is 80ppm (380 - 300).

    Convert 80ppm to a percentage and that's your answer.
    Thank you! I get it, I have no idea why I didn't do that and only couple more hours left :facepalm:
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    (Original post by CoolRunner)
    can you oxidise a ketone?
    Yes, Secondary alcohols are heated to oxidise a ketone
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    (Original post by Whostolemycookie)
    Yes, Secondary alcohols are heated to oxidise a ketone
    You can't oxidise ketone's further though
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    What page is Jan 2013 on guys? Sorry for asking
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    (Original post by abzy1234)
    You can't oxidise ketone's further though
    Nope, and you can't oxidize tertiary alcohols
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    (Original post by Whostolemycookie)
    Nope, and you can't oxidize tertiary alcohols
    Yup, as they don't have a hydrogen atom on the carbon atom to which the -OH group is attached to
 
 
 
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