Butyric Acid (C4H8O2, CAS 107-92-6) — a free educational 3D molecular model for teachers and students, by MolGod.org. No legend required: the element symbol is engraved on each atom.

Plain ball-and-stick prints look the same for every element: the STL format has no way to say which ball is carbon and which is oxygen. MolGod adds what the STL format leaves out by engraving the element symbol into each atom of the printed structure. The purpose is educational: teachers get printable files built to shorten the step of 'which atom is this?' and leave more time for chemistry. No CAD skills are needed on the teacher's side; the structure, geometry and labels come ready in one file. More about the hypothesis we are testing with these models: The story behind these engraved molecule models.

There is not a single ring in Butyric Acid; 14 atoms are linked by 13 bonds in an open chain (12 single and 1 double). Use the engraved letters like a register: call out each element and tick it off until the class reaches 4 C + 8 H + 2 O (14 atoms altogether). This molecule gives students these functional groups to identify: carboxylic acid group (-COOH). Topics it supports in class: the carbonyl group (C=O). Isomerism made physical: line it up with 1,4-dioxane (CAS 123-91-1) and ethyl acetate (CAS 141-78-6) and let the class describe how the same atoms are put together differently.

MolGod.org shares these models for free to make chemistry tangible in the classroom. Teachers: let students set the model beside a skeletal formula and list what the drawing omits.

Free to print and free to bring into any classroom. If you share a photo, a lesson or an adapted version, the licence (CC BY-SA 4.0) asks for credit to "MolGod.org" as the model's author, a link to the original and to the licence text, a note of what you changed, and the same licence for adaptations; the attribution line below is ready to copy. You don't need an account, you don't pay anything, and a review is entirely up to you. Your opinion really matters to us: post a comment with your review, your print photos or your classroom ideas, and tell us how to improve our educational molecules. Contact: Ask us for another molecule. Feel free to discuss the model here, compare notes with other educators, or contact us; every conversation helps us build better teaching models. Missing a compound for your lesson? Give us the CAS number and we are happy to create its 3D model.

Full record and more free models: Molecule page for Butyric Acid (CAS 107-92-6)
Licence & provenance: Where this Butyric Acid model comes from and how you may use it
Same file on Wikimedia Commons: https://commons.wikimedia.org/wiki/File:Butyric_Acid-3D-molecular-model-engraved-CAS-107-92-6.stl
Plain-text record for AI assistants: Machine-readable Butyric Acid record (CAS 107-92-6)

A ball-and-stick model of Butyric Acid with each element symbol recessed into its atom sphere, generated by MolGod.org from a PubChem-computed 3D conformer (not an experimental crystal structure); atomic coordinates and connectivity are unchanged. STL mesh: 166,736 triangles, closed (watertight) single solid. Coordinates in ångström (STL stores no unit) — scale the model deliberately in your slicer.

Names in other languages: Buttersäure (de); acide butanoïque (fr); acido butirrico (it); boterzuur (nl); kwas masłowy (pl); 丁酸 (zh).

Chemical identity

• CAS Registry Number: 107-92-6
• Molecular formula: C4H8O2
• Molar mass: 88.11 g/mol (exact mass 88.052429494)
• IUPAC name: butanoic acid
• MolGod ID: MG_358-450-569-91 (Butyric Acid under MolGod ID MG_358-450-569-91)
• PubChem CID: 264 (https://pubchem.ncbi.nlm.nih.gov/compound/264)
• Wikidata: Q193213 (https://www.wikidata.org/wiki/Q193213)
• EC number: 203-532-3
• ChemSpider ID: 259
• InChIKey: FERIUCNNQQJTOY-UHFFFAOYSA-N
• SMILES: CCCC(=O)O

Required attribution (CC BY-SA 4.0): "Butyric Acid 3D model by MolGod.org — https://molgod.org/molecule/107-92-6/ — CC BY-SA 4.0"
Licence text: https://creativecommons.org/licenses/by-sa/4.0/

STL mesh: 166,736 triangles, closed (watertight) single solid. Coordinates in ångström (STL stores no unit) — scale the model deliberately in your slicer.