How is glycerol (propane-1,2,3-triol) classified by the number of –OH groups it contains?
- Monohydric alcohol
- Dihydric alcohol
- Trihydric alcohol
- Phenol
Show answer and solution
Correct answer: C. Trihydric alcohol
Glycerol has three hydroxyl groups (on C1, C2 and C3), making it a **trihydric** alcohol.
Monohydric carries one –OH (e.g. ethanol)
dihydric two (e.g. ethylene glycol).