Atomic Structure : overview : remember

Summary

Atomic structure describes how atoms are built from protons, neutrons, and electrons, how these subatomic particles are arranged, and how that arrangement determines chemical and physical properties. Central ideas include atomic number and mass, isotopes and ions, electron shells and orbitals, quantum numbers, and the historical evolution from early particle models to the modern quantum mechanical model. Understanding atomic structure underpins periodic trends, bonding, spectroscopy, and many areas of chemistry and materials science.