Sucrose is dextrorotatory,but the mixture obtained after hydrolysis is laevorotatory. Explain.

(N/A) Sucrose is naturally dextrorotatory with a specific rotation of $+66.5^{\circ}$.
Upon hydrolysis,sucrose yields an equimolar mixture of $D$-glucose and $D$-fructose.
The specific rotation of $D$-glucose is $+52.5^{\circ}$ (dextrorotatory),while the specific rotation of $D$-fructose is $-92.4^{\circ}$ (laevorotatory).
The net rotation of the mixture is the average of these two values: $\frac{(+52.5^{\circ}) + (-92.4^{\circ})}{2} = -19.95^{\circ}$.
Since the net rotation is negative,the resulting mixture is laevorotatory. This process is often called the inversion of cane sugar.