What is the IUPAC name of Glycerol?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Propane-1,2,3-triol
The IUPAC name of an alcohol takes the name of the longest carbon chain carrying the –OH groups, with the suffix “-ol”. For more than one –OH group, a multiplying prefix (diol, triol) and a locant for each group are used, and the “e” of the alkane name is kept (propane-1,2,3-triol, not propan-1,2,3-triol).
Glycerol is \( \ce{HOCH2-CH(OH)-CH2OH} \): a three-carbon chain with one –OH group on each of carbons 1, 2 and 3. So its IUPAC name is propane-1,2,3-triol.
NCERT (2026-27 edition):
Nomenclature
Table 7.1: Common and IUPAC Names of Some Alcohols (row)
| Compound | Common name | IUPAC name |
|---|---|---|
| HOCH2–CH(OH)–CH2OH | Glycerol | Propane-1,2,3-triol |
Note: The same/similar question has been asked in different years by NTA as per the details given below:
| 2026 | 2025 | 2024 | 2023 | 2022 |
|---|---|---|---|---|
| – | 30-05 S2 | – | – | 23-08 S1 |