Chapter Twenty-Four

Atomic Structure

Chemistry is the study of the nature and behavior of matter. The atom is the basic building block of matter, representing the smallest unit of a chemical element. An atom in turn is composed of subatomic particles called protons, neutrons, and electrons. The protons and neutrons in an atom form the nucleus, the core of the atom. The electrons exist outside the nucleus in characteristic regions of space called orbitals. All atoms of an element show similar chemical properties and cannot be further broken down by chemical means.