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anonymous

  • one year ago

lease help me loves. a sample of white powder is given to you to identify. You may use the the Benedict test, the Lugol test, the Biuret test, and the Sudan Red test to identify it. 1.what will each test tell you? 2.If the white powder was an starch, how would each of the tests turn out?

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  1. .Sam.
    • one year ago
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    What do you know about these tests?

  2. anonymous
    • one year ago
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    The Benedict test will check for sugars. The Lugol test contains iodine and it turns starch black/ purple. The Biuret test tests for proteins and it turns purple. Finally the Sudan Red test tests for fats.

  3. anonymous
    • one year ago
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    This is the uqestions In a minimum of two paragraphs (10 + sentences), write what each test (Benedict, Lugol, Biuret, and Sudan Red) will tell you.

  4. anonymous
    • one year ago
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    n a minimum of one paragraph (5 + sentences), describe how each test (Benedict, Lugol, Biuret, and Sudan Red) would turn out if each substance was a starch.

  5. .Sam.
    • one year ago
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    So you knew what the tests does, what's the problem? You could use google for reference btw

  6. anonymous
    • one year ago
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    well idk how each test (Benedict, Lugol, Biuret, and Sudan Red) would turn out if each substance was a starch.

  7. anonymous
    • one year ago
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    or what they will tell me im lost

  8. .Sam.
    • one year ago
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    If for example you use biuret's test for starch there won't be any result. You won't produce any colour change or any reaction happen

  9. anonymous
    • one year ago
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    because it only checks for sugars?

  10. .Sam.
    • one year ago
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    Biuret detects presence of peptide bonds. Benedict's tests for reducing sugars

  11. anonymous
    • one year ago
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    what would bendicts result be for starch nothing?

  12. .Sam.
    • one year ago
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    Starch is not reducing sugar but a polysaccharide. And yes, there is a way for benedict's to detect starch, and that is starch has to be hydrolysed to glucose first

  13. anonymous
    • one year ago
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    the color would be brown for benedict right

  14. .Sam.
    • one year ago
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    Blue to Brick red if results are positive

  15. anonymous
    • one year ago
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    ahh i need helping answering the questions above abt the white starch

  16. .Sam.
    • one year ago
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    Benedict test nothing happens or might make little change from teal to green because starch is not reducing sugar. Lugol's test yields positive result from white to black Biuret's test negative shows teal colour.

  17. anonymous
    • one year ago
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    what about sudan red

  18. .Sam.
    • one year ago
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    Red dye will not stain or mix with starch and thus remains separated, if there is lipid or fat Sudan red with stain the fat molecule.

  19. anonymous
    • one year ago
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    so this answers the white starch question right

  20. .Sam.
    • one year ago
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    Yes

  21. anonymous
    • one year ago
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    A sample of a white powder is given to you to identify. You can use the Benedict test, the Lugol test, the Biuret test, and the Sudan Red test to identify it. Answer the questions to report on your analysis plan.

  22. anonymous
    • one year ago
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    how do i answer this one needs two patagraphs In a minimum of two paragraphs (10 + sentences), write what each test (Benedict, Lugol, Biuret, and Sudan Red) will tell you. *You should set up your second paragraph by explaining the scenario you were put in*

  23. anonymous
    • one year ago
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    so far i put this for that one The Benedict test will check for sugars. The Lugol test contains iodine and it turns starch black/ purple. The Biuret test tests for proteins and it turns purple. Biuret detects presence of peptide bonds. Finally the Sudan Red test tests for fats.

  24. anonymous
    • one year ago
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    idk what else to add hmm

  25. .Sam.
    • one year ago
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    You could add "if the results turned out negative, what will happen?" to your answer too

  26. .Sam.
    • one year ago
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    Add in the procedure of how you did the tests. Here are some material that could help you http://www.cpet.ufl.edu/wp-content/uploads/2013/03/Identifying-Macromolecules-Lab.pdf

  27. anonymous
    • one year ago
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    but i dont have to dot he porcedure aha its jst asking what i would do in that scenerio which idk

  28. .Sam.
    • one year ago
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    Yeah the question is asking you about the colour changes and why. Lets say we take Benedict's test for starch. Result will be negative and shows no change in colour from initial blue colour. Then explain why, you'll say because Benedict's tests reducing sugar, starch is non-reducing sugar and therefore doesn't produce any changes in colour

  29. .Sam.
    • one year ago
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  30. anonymous
    • one year ago
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    oh ok i get it now aha thanks very much !!

  31. .Sam.
    • one year ago
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    As for biuret's test for presence of peptide bond. Because starch is not a protein, and has not peptide bound,

  32. .Sam.
    • one year ago
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    no peptide bond, it produces no result for biuret's test with starch

  33. .Sam.
    • one year ago
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    yw :)

  34. David27
    • one year ago
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    sam

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