What percentage of -D-(+)-glucopyranose is found at equilibrium in the aqueous solution?

Step-by-step solution

Ordinary glucose is -glucose, with a fresh aqueous solution has specific rotation, [ ]_D=+110^ . On keeping the solution for sometimes, -glucose slowly changes into an equilibrium mixture of -glucose (36 %) and -glucose ( 64 % ) and the mixture has specific rotation +52.5^