Book excerpt: Atomic and Nuclear Chemistry, Volume 1: Atomic Theory and Structure of the Atom presents the modern ideas of the atomic theory and atomic structure against the background of their historical development. Topics covered include the classification of elements; atoms and electrons; the wave mechanical model of the atom; and the determination of atomic weights. This volume is comprised of six chapters and begins by discussing the origin of the atomic theory, focusing on the role of John Dalton, Avogadro's hypothesis, and the introduction to the laws of chemical combination. The chapters that follow look at the work of the early scientists that led to the development of the periodic table of elements; the use of the Avogadro number to determine the actual masses of atoms and molecules; and the structure of the atom. The essential results of the simple wave mechanical treatment are summarized in the next chapter. This book concludes by considering developments in the determination of atomic weights. Some brief notes on the character and personality of the great scientists who are mentioned throughout the text are included. This book is intended for students and practitioners in the fields of chemistry and physics.