Periodicity & Trends in the Periodic Table

Learn how the periodic table of the elements is structured. Get basic history about its development and learn how periods and groups relate to electrons and atomic mass.

Learn about the periodic properties or trends in the periodic table of the elements.

Elements can be categorized according to their similar properties. Here's a periodic table that organizes the elements according to groups. Click an element symbol and learn about the group to which it belongs.

Learn why sometimes increasing the atomic number of an element doesn't necessarily increase its atomic mass.

Learn about electronegativity, the trends of electronegativity for elements in the periodic table, and how electronegativity relates to chemical bonding.

Learn about the periodic table trends seen for the ionic radius of the elements.

Ionization energy is the energy required to remove an electron from an atom or ion in the gas state. Here's more information about what ionization energy is and what trends in ionization energy you can expect to see on the periodic table.

Learn about the periodic properties or trends in the periodic table of the elements.

Do you understand the trends of periodic table periodicity? Here's a ten question multiple choice quiz you can take to test your knowledge.

Learn what is meant by the metallic character of an element and how metallic character changes as you move across a period or down a group in the periodic table.