Boiling of Sucrose with water in the presence of acid (\( H^+ \)) will give:
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Glucose and Fructose
Sucrose is a disaccharide: one α-D-glucose unit and one β-D-fructose unit joined by a glycosidic linkage between C1 of glucose and C2 of fructose. Boiling with dilute acid hydrolyses this linkage, and one molecule of water splits the disaccharide into its two monosaccharides:
\( \displaystyle \ce{C12H22O11 + H2O} \xrightarrow[\Delta]{\ce{H+}} \ce{C6H12O6}\,(\text{glucose}) + \ce{C6H12O6}\,(\text{fructose}) \)
So the products are an equimolar mixture of D-(+)-glucose and D-(−)-fructose. Sucrose is dextrorotatory, but the mixture is laevorotatory because fructose (−92.4°) turns the plane more than glucose (+52.5°); the product is therefore called invert sugar.
Why the other options are incorrect
Option (2) Cellulose and Glucose — Incorrect. Cellulose is a polysaccharide of thousands of glucose units; hydrolysis breaks molecules down and cannot build a polymer.
Option (3) Cellulose and Fructose — Incorrect. Fructose is formed, but cellulose is not, for the same reason.
Option (4) Starch and Glucose — Incorrect. Starch too is a polysaccharide; glucose is formed, but its partner is fructose.
NCERT (2026-27 edition):
Sucrose
