The modern periodic table has evolved over a long period of time as new discoveries have been made. Learn about the contributions made by different scientists to its development.

Engaging and very informative article that explains what elements are, some of their history, how they are represented, the categories of elements, the periodic table, and how they are structured and classified.

Information about the element Zirconium, atomic number 40. Covers history of its discovery, sources, physical properties, atomic properties, how abundant it is on the Earth, details about permissible exposure, uses, and possible...

Information about the element, Strontium, atomic number 38. Covers its history, sources, physical properties, atomic properties, how abundant it is on the Earth, details about permissible exposure, uses, and possible substitutes.

A short but nice description of nitrogen's uses and properties. Discusses the history of nitrogen and its characteristics.

Webelements offers a nice presentation on erbium, its properties, uses and history, along with basic data. Clearly presented.