Description

This entry presents Naphthalene (C10H8; CAS 91-20-3; PubChem CID 931 (https://pubchem.ncbi.nlm.nih.gov/compound/931)) 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. Biological relevance: Naphthalene, used in mothballs, is recorded as a carcinogen, which links a familiar household use to toxicology (source: Wikidata Q179724 (https://www.wikidata.org/wiki/Q179724), retrieved 2026-10-10). Structure at a glance 18 atoms: 10 C, 8 H 19 bonds: 8 single, 11 aromatic Two 6-membered rings, fused along a shared edge, both aromatic No hydrogen-bond donors or acceptors (computed) No carbon atom is sp3-hybridised Use in teaching Counting task: students tally the engraved symbols (10 C, 8 H; 18 atoms) and rebuild the formula C10H8 from the model alone. Aromaticity: identify the two aromatic rings and the 11 bonds recorded as aromatic. File and printing STL mesh of 245,598 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: 6.117 × 6.117 × 5.09 Å; at scale factor 10 (1 Å to 10 mm, file read in millimetres) the print measures about 61.2 × 61.2 × 50.9 mm. SHA-256: 583d28c8db328fb21998f41305f068ab226b297d46d12152622b580c2e594eb4. Validation InChIKey identical to the PubChem record (PubChem FTP SDF, file dated 2026-10-08): UFWIBTONFRDIAS-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/91-20-3 (https://molgod.org/molecule/91-20-3/?utm_source=nih3d&utm_medium=referral&utm_campaign=edu-3d-models) · Licence and provenance record: molgod.org/licenses/stl/91-20-3 (https://molgod.org/licenses/stl/91-20-3/) · Same file on Wikimedia Commons: File:Naphthalene-3D-molecular-model-engraved-CAS-91-20-3.stl (https://commons.wikimedia.org/wiki/File:Naphthalene-3D-molecular-model-engraved-CAS-91-20-3.stl) MolGod ID: MG_511-082-366-87 (https://molgod.org/id/MG_511-082-366-87) Wikidata: Q179724 (https://www.wikidata.org/wiki/Q179724) EC number: 202-049-5 ChemSpider ID: 906 IUPAC name: naphthalene InChIKey: UFWIBTONFRDIAS-UHFFFAOYSA-N SMILES: C1=CC=C2C=CC=CC2=C1 Molar mass 128.17 g/mol (exact mass 128.062600255) Licence: CC BY-SA 4.0 (licence text (https://creativecommons.org/licenses/by-sa/4.0/)). Required attribution: "Naphthalene 3D model by MolGod.org — https://molgod.org/molecule/91-20-3/ — CC BY-SA 4.0".