Periodic Table of Elements
The periodic table of elements is a tabular arrangement of all known chemical elements, organized by increasing atomic number, electron configurations, and recurring chemical properties. Each element is represented by its chemical symbol, atomic number, and atomic mass. The table is divided into rows called periods and columns known as groups. Elements in the same group exhibit similar chemical behaviors due to their comparable valence electron configurations.
The periodic table, first devised by Dmitri Mendeleev in 1869, has undergone several refinements as new elements have been discovered and our understanding of atomic structure has advanced. It serves as a fundamental framework in chemistry and physics, allowing scientists to predict the properties of elements, understand chemical reactions, and explore the relationships between different elements. The modern periodic table includes metals, nonmetals, and metalloids, as well as specific families like noble gases, halogens, and transition metals, each with distinct characteristics and uses in various scientific and industrial applications.