Periodic Table Notes Periodic Table Organizational chart where elements are classified according to the chemical properties, protons, and valence electrons Proton The subatomic particle that identifies the element. Valence Electron Electrons that are on the outermost energy level. Period The horizontal rows across the periodic table. Represent the number of energy levels (of electrons) Atomic number increases across the table from right to left. Groups (Families) Vertical columns on the periodic table Represent the number of valence electrons and how an element reacts with other elements. Each element in the group will react in a similar way. Families include: Alkali metals, Alkali earth metals, Boron family, Carbon family, Nitrogen family, Oxygen family, Halides, and Noble gases. Metals Metals are the Majority of the Periodic table. They have traits like High Luster (shiny), Malleability (bend before breaking) , electrical conductors, generally solid at room temperature. Non-Metals Nonmetals have traits such as: Low luster, easily break or are a gas, Poor conductors (insulators). Metalloids Metalloids or semi-metals have some traits of both metals and non-metals. Such traits as: Generally a metallic look but are brittle, soft, do not conduct heat or insulate very well, Conduct electricity sometimes (good for electronics)