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    Hello, can someone help me with this 6 marker?
    "Explain why benzene absorbs in the ultraviolet while Orange II absorbs visible light"
    I'm thinking it's something to do with the energy level difference, but can barely scrape 3 marks nevermind 6. Any help greatly appreciated thank you
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    which topic is this in?? and is this F334 or F335?
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    F334 and I'm not sure I think colours by design?
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    (Original post by MellyAmber)
    Hello, can someone help me with this 6 marker?
    "Explain why benzene absorbs in the ultraviolet while Orange II absorbs visible light"
    I'm thinking it's something to do with the energy level difference, but can barely scrape 3 marks nevermind 6. Any help greatly appreciated thank you
    I think this is because of the delocalisation of electrons in benzene and orange II. Organic molecules with a greater degree of delocalisation require a lower excitation energy.

    The more double bonds and aromatic rings that they have the more delocaliation of electrons can occur. This is the case for orange 2 as it has more aromatic groups (benzene rings) and i think it also has a Nitrogen bonded to a nitrogen?
    As orange II will have a lower excitation energy is will absorb lower a lower frequency of light given by the equation (change in energy=Plancs constant * frequency.) as it transitions to a higher energy level.

    Therefore orange ii absorbs low energy visible light and benzene absorbs the higher energy UV (Benzene has less delocaiisation so greater excitation energy.

    Are you doing salter`s OCR B?
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    (Original post by SamuelN98)
    I think this is because of the delocalisation of electrons in benzene and orange II. Organic molecules with a greater degree of delocalisation require a lower excitation energy.

    The more double bonds and aromatic rings that they have the more delocaliation of electrons can occur. This is the case for orange 2 as it has more aromatic groups (benzene rings) and i think it also has a Nitrogen bonded to a nitrogen?
    As orange II will have a lower excitation energy is will absorb lower a lower frequency of light given by the equation (change in energy=Plancs constant * frequency.) as it transitions to a higher energy level.

    Therefore orange ii absorbs low energy visible light and benzene absorbs the higher energy UV (Benzene has less delocaiisation so greater excitation energy.

    Are you doing salter`s OCR B?

    Ooo thank you very helpful

    Yes, I am and I absolutely hate it... are you?
    If so is the coursework the death of you?
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    (Original post by MellyAmber)
    Ooo thank you very helpful

    Yes, I am and I absolutely hate it... are you?
    If so is the coursework the death of you?
    Yeah.
    I have finished it now but dread to think of the amount of time a spent on it.
    Whats your project on?

    (By the way the explanation for the question you asked is on page 160 of chemical ideas textbook if you have it)
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    (Original post by SamuelN98)
    Yeah.
    I have finished it now but dread to think of the amount of time a spent on it.
    Whats your project on?

    (By the way the explanation for the question you asked is on page 160 of chemical ideas textbook if you have it)
    Yes oh my it takes for ever, really wish I did OCR A :/
    I have still not finished eeek.
    I did sodium thiosulfate and hcl (the easiest one i thought)
    What about you?

    Thanks so much

    What you applying to uni for?
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    (Original post by MellyAmber)
    Yes oh my it takes for ever, really wish I did OCR A :/
    I have still not finished eeek.
    I did sodium thiosulfate and hcl (the easiest one i thought)
    What about you?

    Thanks so much

    What you applying to uni for?
    My project was on the reaction of potassium Manganate and Ethanedioc acid, the auto-catalytic effects. Confused me a bit, wish a chose something i understood a bit better to be honest.

    Haven`t chosen a firm uni yet. I applied for chemistry at lough-borough, Birmingham, but also for chemical engineering.

    What course are you planning to do?
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    (Original post by SamuelN98)
    My project was on the reaction of potassium Manganate and Ethanedioc acid, the auto-catalytic effects. Confused me a bit, wish a chose something i understood a bit better to be honest.

    Haven`t chosen a firm uni yet. I applied for chemistry at lough-borough, Birmingham, but also for chemical engineering.

    What course are you planning to do?
    Oo that sounds interesting. Ah I see, at least you wouldn't have the problem of having information that wasn't at A level standard.
    Excellent, both UNI's seem amazing.
    I have applied for biomed and firmed Warwick and insured Kent.
    Stress is on now, right?
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    (Original post by MellyAmber)
    Oo that sounds interesting. Ah I see, at least you wouldn't have the problem of having information that wasn't at A level standard.
    Excellent, both UNI's seem amazing.
    I have applied for biomed and firmed Warwick and insured Kent.
    Stress is on now, right?
    I visited Warwick, really liked the campus. Looks so new compared to the others i have seen.
    I know what you mean about the stress, been studying like a maniac all week.
    Good luck, and happy studying.
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    (Original post by SamuelN98)
    I visited Warwick, really liked the campus. Looks so new compared to the others i have seen.
    I know what you mean about the stress, been studying like a maniac all week.
    Good luck, and happy studying.

    That's great to hear Back at you! Give yourself down time also!
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    (Original post by MellyAmber)
    That's great to hear Back at you! Give yourself down time also!
    Hey.
    By the way do you know if there is an official thread for the OCR B exams?
    All i could was the OCR A one
    Thanks.
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    (Original post by MellyAmber)
    ...at least you wouldn't have the problem of having information that wasn't at A level standard...
    What did you write about that wasn't A-level standard?
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    (Original post by SamuelN98)
    Hey.
    By the way do you know if there is an official thread for the OCR B exams?
    All i could was the OCR A one
    Thanks.
    Not that have seen, I don't think Salter's is anywhere near as popular
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    (Original post by Pigster)
    What did you write about that wasn't A-level standard?
    Need to be careful as HCl and thio is a gcse reaction
 
 
 
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