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    Compounds A and B are D-aldopentoses which by oxidation with HNO3 give optically active acids. What are A and B?

    Is the correct answer ribose and arabinose
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    Why those two?
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    (Original post by Pigster)
    Why those two?
    I chose them randomly. Is that the correct answer or not?
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    One of your answers is correct.

    A classic teacher response now is to point out that if I were simply to tell you the answer, you'd learn nothing. If you had to research it for yourself, you're much more likely to understand and remember.

    It didn't take me long to google the answer, time I didn't mind wasting as I was interested in the answer. I don't want to just do your homework for you.

    Your Q perhaps should have mentioned that it forms a diacid.
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    (Original post by BioOx)
    I chose them randomly. Is that the correct answer or not?
    If you chose them randomly it doesn't matter if you're right or not. Either way you don't understand what you're supposed to.
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    (Original post by Pigster)
    One of your answers is correct.

    A classic teacher response now is to point out that if I were simply to tell you the answer, you'd learn nothing. If you had to research it for yourself, you're much more likely to understand and remember.

    It didn't take me long to google the answer, time I didn't mind wasting as I was interested in the answer. I don't want to just do your homework for you.

    Your Q perhaps should have mentioned that it forms a diacid.
    Well, I know that for a molecule to be optically active it must have a stereocenter, a carbon that has 4 different groups or atoms attached. So is arabinose is oxidized it will give an optically active acid but if ribose is oxidized it wont, right?
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    Correct, so which is the other one?
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    (Original post by Pigster)
    Correct, so which is the other one?
    xylose ?
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    (Original post by BioOx)
    xylose ?
    Are you guessing again?
 
 
 
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