MolDraw › 3D molecule models › Acetic acid structure
Acetic acid structure and 3D model (C2H4O2)
Acetic acid (ethanoic acid) is a methyl group attached to a carboxylic acid group. It is the acid in vinegar.
Drag to rotate · pinch or scroll to zoom. 3D coordinates: computed with RDKit (ETKDG conformer, force-field optimised).
Acetic acid at a glance
| Formula | C2H4O2 |
|---|---|
| Molar mass | 60.05 g/mol |
| IUPAC name | acetic acid |
| Atoms / bonds | 8 / 7 |
| H-bond donors / acceptors | 1 / 1 |
| logP (estimated) | 0.1 |
| SMILES | CC(=O)O |
| InChIKey | QTBSBXVTEAMEQO-UHFFFAOYSA-N |
| PubChem | 176 |
What the 3D model of Acetic acid shows
The model contains 8 atoms (4 heavy atoms and 4 hydrogens) joined by 7 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 1 and accept 1 hydrogen bonds, and its estimated logP of 0.1 means it is fairly balanced between water and fat. Its topological polar surface area is 37 Ų.
Shape and bond angles
| Atom(s) | Geometry / hybridisation | Angles & lengths |
|---|---|---|
| carboxyl carbon | Trigonal planar, sp² | ≈ 120° |
| methyl carbon | Tetrahedral, sp³ | ≈ 109.5° |
| hydroxyl O | Bent, sp³-like | ≈ 106° (C–O–H) |
Is Acetic acid polar?
Yes. The COOH group is polar and forms hydrogen bonds, so acetic acid mixes with water in all proportions. Pure acetic acid forms hydrogen-bonded dimers.
Elemental composition of C2H4O2
| Element | Atoms | Mass (g/mol) | Mass % |
|---|---|---|---|
| Carbon (C) | 2 | 24.022 | 40.00% |
| Hydrogen (H) | 4 | 4.032 | 6.71% |
| Oxygen (O) | 2 | 31.998 | 53.28% |
Calculated from IUPAC standard atomic weights. Check any formula with the molar mass calculator.
Uses of acetic acid
- Main acid in vinegar (about 4–8% in water)
- Raw material for vinyl acetate and cellulose acetate
- Common solvent and reagent in labs
Interesting facts
- Pure acetic acid is called glacial acetic acid because it freezes into ice-like crystals at about 17 °C.
- It is a weak acid with a pKa of about 4.76.
- Most acetic acid is now made by reacting methanol with carbon monoxide.
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Open MolDraw editorFrequently asked questions
What is the structure of Acetic acid?
Acetic acid (ethanoic acid) is a methyl group attached to a carboxylic acid group. It is the acid in vinegar. Its SMILES is CC(=O)O.
Is acetic acid a strong or weak acid?
Weak. Only a small fraction of its molecules lose H⁺ in water (pKa about 4.76).
What is the difference between acetic acid and vinegar?
Vinegar is a dilute solution of acetic acid in water, with small amounts of flavour compounds.
What is the chemical formula and molar mass of Acetic acid?
Acetic acid is C2H4O2 with a molar mass of 60.05 g/mol. It contains 8 atoms: 2 carbon, 4 hydrogen, 2 oxygen.
What is the IUPAC name of Acetic acid?
The IUPAC name is acetic acid.
How do I draw Acetic acid?
Open the MolDraw editor, paste the SMILES CC(=O)O or type "Acetic acid" in name search, and the structure is drawn for you. You can then export it as PNG, SVG, MOL or CDXML.