Molecular geometry is a center piece to a student’s understanding of intermolecular forces. Unfortunately, many students don’t have the special skills to “see” the geometry without a model kit. We use a model kit in our laboratories, but there are not enough of them nor are there funds to purchase more. The students are unable to use these during their study time. It is helpful for students to have access to a model kit while they are studying.
So, I have created a VSEPR flat pack. This is an inexpensive paper model kit that students can use at home and personalize to indicate different types of atoms and electron domains. It is easily assembled / disassembled for storage in a flat envelope.
Video 1: Cutting out the Flat Pack Model Kit, ChemEd X Vimeo Channel, June 12, 2023.
Prep time: 10-20 minutes to cut-out.
1. Print out pages of the flat pack on copy paper or card stock.
- There are 2 pages for the minimum model set covering linear, trigonal planar, tetrahedral, trigonal pyramidal and octahedral geometries.
- More can be printed out to distinguish between different molecular geometries and electron domain geometry.
- These can be enlarged and affixed to foam core for a classroom set.
2. Color the circles
- Large circles = lone electron pairs
- Smaller circle = atoms
3. Cut out the flat pack
- Simple straight lines
- Cut along dotted lines
- Informal cuts around the atoms.
- This is a quick representation.
- Cut around circles indicating atoms/ electron pairs (best representation)
- Cut slits
4. Assemble by connecting along the slits.
- Draw electron dot diagram for the compound
- Determine number of electron domains around the central atom.
- Choose the geometry that matches the electron domains.
- Determine molecular geometry
- Look at atoms in same structure
- Look at lone electron pairs (different color, large circles)
- Determine polarity based on geometry.
Look at the atom (same circles) arrangement.
Provide students with printed copies of the models that they can cut out themselves.
Tennessee Technological University Chemistry Department
Modeling in 9–12 builds on K–8 and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed worlds.
Modeling in 9–12 builds on K–8 and progresses to using, synthesizing, and developing models to predict and show relationships among variables between systems and their components in the natural and designed worlds. Use a model to predict the relationships between systems or between components of a system.