Navigating the Periodic Table: A Beginner's Guide
The periodic table organizes all 118 known elements by atomic number (number of protons). Each element has a unique symbol (e.g., H for Hydrogen, O for Oxygen, Fe for Iron).
Periods (rows): There are 7 periods. Moving left to right, atomic number increases. Elements in the same period have the same number of electron shells.
Groups (columns): There are 18 groups. Elements in the same group have similar chemical properties because they have the same number of valence electrons.
Major categories: Alkali metals (Group 1, very reactive), Alkaline earth metals (Group 2), Transition metals (Groups 3-12), Halogens (Group 17, very reactive nonmetals), Noble gases (Group 18, inert).
Reading an element card: Atomic number (top), Symbol (center), Name, Atomic mass (bottom). For example, Carbon: #6, C, Carbon, 12.011 g/mol. Electron configuration: [He] 2s² 2p².
Use our Interactive Periodic Table in the Chemistry category — click any element to see its full details including atomic mass, electron configuration, and category.