How to Make a Carbon Atom Model From Pompoms & Beads

The carbon atom’s nucleus contains six positively charged protons and six electrically neutral neutrons. Six negatively charged electrons surround the nucleus. Although it’s easy to model these atomic particles with craft materials, it’s important to understand why any such model is inaccurate. First, the scale is wrong. If a carbon nucleus were the size of a pinhead, the space containing electrons would be almost five times the size of a football field. Secondly, simple models imply that electrons orbit the nucleus like planets around the sun, occupying particular places at specific times. In fact, electrons are wavelike particles with no individual position; they exist in a cloud made up of orbital shells with different energy levels. Instead of thinking of the electrons in this model as objects in a specific place, think of them as quantities. Six electrons form the atom’s electron cloud; two inhabit the first energy level and four inhabit the second.

Things You'll Need

• 6 red pompoms, 1 inch
• 6 white pompoms, 1 inch
• White tacky glue
• Small safety pin
• 22-gauge craft wire
• Measuring tape or yardstick
• Wire cutters or scissors
• Electrical tape (optional)
• Cotton balls
• 6 black beads

Instructions

1. Glue the sides of four random pompoms together to form a square. Glue four more pompoms to the top of this square to form a cube. Glue a pompom to the center of the cube’s top side. Repeat this step on the cube’s bottom, right and left sides. This ball represents the carbon atom’s nucleus; the red pompoms are protons and the white ones are neutrons.

2. Attach a safety pin to the nucleus. Fasten one end of a 3-foot length of craft wire to the safety pin. This will enable you to hang your completed model.

3. String two black beads onto a second 3-foot length of wire. Bend the wire into a circle measuring roughly 10 inches in diameter. Twist about 1 inch of the circle’s ends around the wire attached to the nucleus so that the circle is centered around the nucleus. Tape or glue the twisted wires to hold them in place. Move one bead to the left side of the circle and glue it in place. Glue the other bead to the opposite side. These beads represent the two electrons inhabiting the carbon atom’s first energy level.

4. Glue wisps of cotton along the wire circle. The fuzzy material represents the cloud in which the atom’s two lower-energy electrons are most likely to be found.

5. String four black beads onto a 5-foot length of wire. Bend the wire into a circle measuring roughly 16 inches in diameter. Twist about 1 inch of the circle’s ends around the wire attached to the nucleus, making sure the circle is centered around the nucleus and the smaller circle. Turn this circle until it’s perpendicular to the smaller circle. Tape or glue the twisted wires to hold them in place. Space the beads out evenly around the circle and glue them in place. This represents the four electrons inhabiting the carbon atom’s second energy level.

6. Glue wisps of cotton to the larger wire circle to represent the cloud in which the atom’s four higher-energy electrons are most likely to be found.

Tips & Warnings

• In this model, the nucleus is three-dimensional and the energy levels are cross sections. In reality, the electron cloud completely surrounds the nucleus.

• If you need to hang your model from a high ceiling, increase the length of the wire in Step 2.

References

• Chemguide: A Simple View of Atomic Structure
• Foundations of Astronomy; Michael A. Seeds and Dana Backman
• Chemguide: Electronic Structure and Atomic Orbitals
• University of Illinois at Urbana-Champaign Department of Physics: Q & A: How to Build a Model Atom