The periodic table of elements, first encountered by many of us at school, provides an arrangement of the chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties, and divided into periodic trends. In this Very Short Introduction Eric Scerri looks at the trends in properties of elements that led to the construction of the table, and shows how the deeper meaning of the table's structure gradually became apparent with the development of atomic theory and, in particular, quantum mechanics, which underlies the behaviour of all of the elements and their compounds. This new edition, publishing in the International Year of the Periodic Table, celebrates the completion of the seventh period of the table, with the ratification and naming of elements 113, 115, 117, and 118 as nihonium, moscovium, tennessine, and oganesson. Eric Scerri also incorporates new material on recent advances in our understanding of the origin of the elements, as well as developments concerning group three of the periodic table. ABOUT THE SERIES: The Very Short Introductions series from Oxford University Press contains hundreds of titles in almost every subject area. These pocket-sized books are the perfect way to get ahead in a new subject quickly. Our expert authors combine facts, analysis, perspective, new ideas, and enthusiasm to make interesting and challenging topics highly readable.