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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
`150.7 (X) + 52.8(1 + X) = + 80 .2`
`150.7 X + 52.8 - 52.8 X = + 80.2`
`97.9 X = 27.4`
`X = 0.279 = 0.28`
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