Question

When the α-form of glucose is dissolved in water and allowed to rest, what will be the percentage of β-form in this solution after some time?

(a) 0

(b) 36

(c) 64

(d) 100

I had been asked this question by my school teacher while I was bunking the class.

I want to ask this question from Biomolecules Carbohydrates in chapter Biomolecules of Chemistry – Class 12

Answer 1

Correct choice is (c) 64

Explanation: When either α or β forms of glucose are dissolved in water and are allowed to stand, an equilibrium mixture of both forms is formed (36% α-form and 64% β-form). This is due to a spontaneous change in specific rotation of an optically active compound with time to an equilibrium value. This phenomenon is called as mutarotation.