Atomic size refers to how big an atom is, and we usually measure it by its atomic radius. The atomic radius is the average distance from the center of the atom (nucleus) to the outer edge where the electrons are.
Key Points:
- Very Small: Atomic radii range from about 30 to 300 picometers (pm), which are incredibly tiny parts of a meter.
- Not a Perfect Sphere: Electrons move around the nucleus in areas called orbitals, not in perfect circles. So, the atomic radius is just an average distance, not an exact edge.
- Varies by Element: Different elements have different atomic sizes. Atoms with more protons and electrons usually have larger radii because their electrons are further away from the nucleus.
