Among the following, which one is a disaccharide?
Answer & explanation
Correct answer: option 3
The correct answer is Option (3) → Maltose
Maltose is a disaccharide: on hydrolysis it gives two molecules of α-D-glucose.
\( \ce{C12H22O11 + H2O -> 2C6H12O6} \)
Why the other options are incorrect
Option (1) Glucose — Incorrect. A monosaccharide; it cannot be hydrolysed into simpler sugars.
Option (2) Glycogen — Incorrect. A polysaccharide, the storage carbohydrate of animals, made of a large number of glucose units.
Option (4) Starch — Incorrect. A polysaccharide, the storage carbohydrate of plants, which gives a large number of glucose units on hydrolysis.
NCERT (2026-27 edition):
Classification of Carbohydrates – …
Maltose
“Another disaccharide, maltose is composed of two α-D-glucose units in which C1 of one glucose (I) is linked to C4 of another glucose unit (II). The free aldehyde group can be produced at C1 of second glucose in solution and it shows reducing properties so it is a reducing sugar.”
Note: The same/similar question has been asked in different years by NTA as per the details given below:
| 2026 | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| – | – | – | – | 23-08 S1 10-08 S1 |