This entry presents Ethylbenzene (C8H10; CAS 100-41-4; PubChem CID 7500) as a 3D-printable ball-and-stick model in which every atom carries its engraved element symbol (C, H), so the model can be read without a colour key. Atomic coordinates come from the PubChem-computed 3D conformer (not an experimental crystal structure); coordinates and connectivity are unchanged.

Structure at a glance

• 18 atoms: 8 C, 10 H

• 18 bonds: 12 single, 6 aromatic

• One aromatic 6-membered ring

• No hydrogen-bond donors or acceptors (computed)

• Fraction of sp3-hybridised (tetrahedral) carbon atoms: 0.25 (computed)

Use in teaching

• Counting task: students tally the engraved symbols (8 C, 10 H; 18 atoms) and rebuild the formula C8H10 from the model alone.

• Aromaticity: identify the aromatic ring and the 6 bonds recorded as aromatic; the model draws them as one Kekulé structure (alternating single and double bonds), while in the real molecule they are delocalised, intermediate between single and double.

File and printing

STL mesh of 218,500 triangles, a closed (watertight) single solid. Coordinates are in ångström and STL stores no unit, so scale the model deliberately in your slicer. Measured bounding box: 5.658 × 5.827 × 4.697 Å; at scale factor 10 (1 Å to 10 mm, file read in millimetres) the print measures about 56.6 × 58.3 × 47.0 mm. SHA-256: 17b45c7fc46c0d23f9a0d2f86088998a6c950ca8b1d5ce3110abe4f94371a438.

Validation

• InChIKey identical to the PubChem record (PubChem FTP SDF, file dated 2026-10-08): YNQLUTRBYVCPMQ-UHFFFAOYSA-N

• Molecular formula and hydrogen-bond donor/acceptor counts identical to PubChem

• Mesh: triangle count in the header equals the actual count; 0 edges not shared by exactly two triangles; 1 connected solid; SHA-256 equal to the published file

Source, licence and identifiers

Full record: molgod.org/molecule/100-41-4 · Licence and provenance record: molgod.org/licenses/stl/100-41-4 · Same file on Wikimedia Commons: File:Ethylbenzene-3D-molecular-model-engraved-CAS-100-41-4.stl

• MolGod ID: MG_553-016-871-43

• Wikidata: Q409184

• EC number: 202-849-4

• ChemSpider ID: 7219

• IUPAC name: ethylbenzene

• InChIKey: YNQLUTRBYVCPMQ-UHFFFAOYSA-N

• SMILES: CCC1=CC=CC=C1

• Molar mass 106.16 g/mol (exact mass 106.078250319)

Licence: CC BY-SA 4.0 (licence text). Required attribution: "Ethylbenzene 3D model by MolGod.org — https://molgod.org/molecule/100-41-4/ — CC BY-SA 4.0".