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The optical rotation of the alpha form o...

The optical rotation of the `alpha` form of a pyranose is + 150.70, that of the `beta` form is +52.80. In solution an equlibrium mixture of the anomers has an optical rotation of +80.20. The percentage of the `alpha` form at equilibrium is

A

0.28

B

0.32

C

0.68

D

0.72

Text Solution

Verified by Experts

The correct Answer is:
A
Let the percentage of `alpha`- form =x (say) , Then the percentage of `beta`- form = (100-x)
`:. ({x xx 150.7} xx {(100-x)52.8})/(100) = 80.20, x = 28` percentage of `alpha`- from = 28%
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AAKASH SERIES-CARBOHYDRATES-Practice Sheet-1
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  2. Which of the following compounds is a beta- ketohexafuranose?

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  3. The optical rotation of the alpha form of a pyranose is + 150.70, that...

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  5. Which of the following statements is correct?

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  6. Which of the following reagents is useful to distinguish between gluco...

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  7. Which of the following is correct statement?

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  8. Which of the following statement is/are correct?

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  9. What is /are the major product (s) in the reaction below?

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  10. Which of the following statements is/are correct

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  11. C(6)H(12)O(6) can be glucose or Fructose C(6)H(12)O(6) overset(HCN)rar...

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  12. C(6)H(12)O(6) can be glucose or Fructose C(6)H(12)O(6) overset(HCN)rar...

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  13. C(6)H(12)O(6) can be glucose or Fructose C(6)H(12)O(6) overset(HCN)rar...

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  14. Monosaccharides and disaccharides in which aldehyde group is free redu...

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  15. Monosaccharides and disaccharides in which aldehyde group is free redu...

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  16. Monosaccharides and disaccharides in which aldehyde group is free redu...

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  17. Match the following columns

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  18. Match the following columns

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  19. The minimum number of carbon atoms that should present in a carbohydra...

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  20. The number of chiral centers in the open chain structure of glucose is

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