Question

Give scientific reasons:

Hydrolysis of sucrose is called inversion.

Answer 1

1) Sucrose (C₁₂H₂₂O₁₁) is dextrorotatory (+66.5°). On hydrolysis with dilute acid or an enzyme called invertase, sucrose gives equimolar mixture of D-(+)-glucose and D-(–)-fructose.

\[\ce{\underset{\text{Sucrose}}{C12H22O11} + H2O ->[H+][\triangle]\underset{\text{D-(+)-Glucose}}{C6H12O6} + \underset{\text{D-(–)-Fructose}}{C6H12O6}}\]

2) Since the laevorotation of fructose (–92.4°) is larger than the dextrorotation of glucose (+52.7°), the hydrolysis product has net laevorotation.
Hence, hydrolysis of sucrose is also called inversion of sucrose.