Periodic table - Wikipedia
https://en.wikipedia.org/wiki/Periodic_tableThe periodic table, also known as the periodic table of (the) chemical elements, is a tabular display of the chemical elements. It is widely used in chemistry, physics, and other sciences, and is generally seen as an icon of chemistry. It is a graphic formulation of the periodic law, which states that the properties of the chemical elements exhibit a periodic dependence on their atomic numbers.
How to Read the Periodic Table | AMNH
www.amnh.org › how-to-read-the-periodic-tableTo keep track of the elements, scientists use the Periodic Table, a chart that shows all the elements. ( Click here for a pdf version of the Periodic Table.) Scientists can quickly find out basic information about an element just by looking at the Periodic Table. There are over 100 known atoms — one for each of the known elements.
Periodic Table of Elements - PubChem
https://pubchem.ncbi.nlm.nih.gov/periodic-tableThe creator of the periodic table, Dmitri Mendeleev, in 1869 began collecting and sorting known properties of elements, like he was playing a game, while traveling by train. He noticed that there were groups of elements that exhibited similar properties, but he also noticed that there were plenty of exceptions to the emerging patterns.