Ammonia (CAS 7664-41-7): engraved ball-and-stick 3D molecular model (STL)
Abstract
This entry presents Ammonia (H3N; CAS 7664-41-7; PubChem CID 222) as a 3D-printable ball-and-stick model in which every atom carries its engraved element symbol (H, N), 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 4 atoms: 3 H, 1 N 3 bonds, all single No rings (open-chain structure) One hydrogen-bond donor and one acceptor (computed) Use in teaching Counting task: students tally the engraved symbols (3 H, 1 N; 4 atoms) and rebuild the formula H3N from the model alone. File and printing STL mesh of 38,454 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: 1.848 × 1.793 × 2.047 Å; at scale factor 10 (1 Å to 10 mm, file read in millimetres) the print measures about 18.5 × 17.9 × 20.5 mm. SHA-256: 6fb69c04c68ceec4d05fda851f476208a570a93becc1fc20e4f71b548db5eb65. Validation InChIKey identical to the PubChem record (PubChem FTP SDF, file dated 2026-10-08): QGZKDVFQNNGYKY-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/7664-41-7 · Licence and provenance record: molgod.org/licenses/stl/7664-41-7 · Same file on Wikimedia Commons: File:Ammonia-3D-molecular-model-engraved-CAS-7664-41-7.stl MolGod ID: MG_380-302-726-03 Wikidata: Q4087 EC number: 231-635-3 ChemSpider ID: 217 IUPAC name: azane InChIKey: QGZKDVFQNNGYKY-UHFFFAOYSA-N SMILES: N Molar mass 17.031 g/mol (exact mass 17.026549100) Licence: CC BY-SA 4.0 (licence text). Required attribution: "Ammonia 3D model by MolGod.org — https://molgod.org/molecule/7664-41-7/ — CC BY-SA 4.0".