The mass of an atom is concentrated in the nucleus—a small, dense sphere with a diameter about 1/100,000 of that atom, meaning that most of the atom is empty space! In the Mapping Atomic Structure: Building a Scale Model of an Atom—ChemTopic™ Lab Activity, translate these dimensions into a real-world scale model using basketballs and a map of Chicago. Available as part of the Atomic and Electron Structure—ChemTopic™ Labs digital collection. Click the Price link for digital collection pricing.