MolDraw › 3D molecule models › Paracetamol structure
Paracetamol structure and 3D model (C8H9NO2)
Paracetamol (acetaminophen) is a phenol with an acetamide group on the opposite side of the ring (para). The amide and OH groups lie almost in the plane of the benzene ring.
Drag to rotate · pinch or scroll to zoom. 3D coordinates: computed with RDKit (ETKDG conformer, force-field optimised).
Paracetamol at a glance
| Formula | C8H9NO2 |
|---|---|
| Molar mass | 151.16 g/mol |
| IUPAC name | N-(4-hydroxyphenyl)acetamide |
| Atoms / bonds | 20 / 20 |
| H-bond donors / acceptors | 2 / 2 |
| logP (estimated) | 1.4 |
| SMILES | CC(=O)NC1=CC=C(C=C1)O |
| InChIKey | RZVAJINKPMORJF-UHFFFAOYSA-N |
| PubChem | 1983 |
What the 3D model of Paracetamol shows
The model contains 20 atoms (11 heavy atoms and 9 hydrogens) joined by 20 bonds; in ball-and-stick mode every stick is one bond, and double or aromatic bonds are drawn as multiple sticks. Switch to space-filling to see the molecule as its electron cloud, scaled to van der Waals radii: this is the shape other molecules actually "feel". It can donate 2 and accept 2 hydrogen bonds, and its estimated logP of 1.4 means it is fairly balanced between water and fat. Its topological polar surface area is 49 Ų.
Shape and bond angles
| Atom(s) | Geometry / hybridisation | Angles & lengths |
|---|---|---|
| ring carbons | Trigonal planar, sp²; planar ring | 120° |
| amide C=O carbon | Trigonal planar, sp² | ≈ 120° |
| amide N | Trigonal planar (partial double bond to C=O) | ≈ 120° |
| acetyl CH₃ | Tetrahedral, sp³ | ≈ 109.5° |
Is Paracetamol polar?
Yes, moderately. The OH and amide N–H can both donate hydrogen bonds, but the benzene ring limits how well it dissolves in water.
Elemental composition of C8H9NO2
| Element | Atoms | Mass (g/mol) | Mass % |
|---|---|---|---|
| Carbon (C) | 8 | 96.088 | 63.56% |
| Hydrogen (H) | 9 | 9.072 | 6.00% |
| Nitrogen (N) | 1 | 14.007 | 9.27% |
| Oxygen (O) | 2 | 31.998 | 21.17% |
Calculated from IUPAC standard atomic weights. Check any formula with the molar mass calculator.
Uses of paracetamol
- Pain relief and fever reduction
- Common ingredient in cold and flu remedies
- Example of an amide made from an amine and acetic anhydride
Interesting facts
- Paracetamol is called acetaminophen in the US and Canada.
- Unlike ibuprofen and aspirin, it has little anti-inflammatory effect.
- It is made by acetylating 4-aminophenol with acetic anhydride.
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Open MolDraw editorFrequently asked questions
What is the structure of Paracetamol?
Paracetamol (acetaminophen) is a phenol with an acetamide group on the opposite side of the ring (para). The amide and OH groups lie almost in the plane of the benzene ring. Its SMILES is CC(=O)NC1=CC=C(C=C1)O.
What functional groups are in paracetamol?
A phenol (OH on the ring), a secondary amide (NH–C=O) and a benzene ring.
Is paracetamol the same as acetaminophen?
Yes. They are two names for the same molecule, N-(4-hydroxyphenyl)acetamide.
What is the chemical formula and molar mass of Paracetamol?
Paracetamol is C8H9NO2 with a molar mass of 151.16 g/mol. It contains 20 atoms: 8 carbon, 9 hydrogen, 1 nitrogen, 2 oxygen.
What is the IUPAC name of Paracetamol?
The IUPAC name is N-(4-hydroxyphenyl)acetamide.
How do I draw Paracetamol?
Open the MolDraw editor, paste the SMILES CC(=O)NC1=CC=C(C=C1)O or type "Paracetamol" in name search, and the structure is drawn for you. You can then export it as PNG, SVG, MOL or CDXML.