On hydrolysis with dilute aqueous sulphuric acid, sucrose gives a equimolar mixture of D- (+) glucose and D-(-)-fructose.
C12H22O11
sucrose
+H2O
H2SO4
→
C6H12O6
D−(+)‌glucose
+
C6H12O6
D−(−)‌fructose
Sucrose is dextrorotatory but after hydrolysis gives dextrorotatory glucose and laevorotatory fructose, laevorotatory fructose is more, so the mixture is laevorotatory.