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The optical rotation of the a form of a ...

The optical rotation of the a form of a pyranose is` +150.7^@`, that of the `beta`-form is `+52.8^@`. In solution an equilibrium mixture of these anomers has an optical rotation of ` + 80.2^@`. The percentage of the c-form in equilibrium mixture 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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