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The optical rotation of the alpha-form o...

The optical rotation of the `alpha`-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 precentage of the `alpha`-form in equilibrium mixture is :

A

`28%`

B

`32%`

C

`68%`

D

`72%`

Text Solution

Verified by Experts

The correct Answer is:
A
`150.7 (X) + 52.8 (1-X) = +80.2`
`150.7X + 52.8X = +80.2`
`97.9X = 27.4`
`X = 0.279 = 0.28`
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