Mendeleev’s periodic table, published in 1869, was a vertical chart that organized 63 known elements by atomic weight. This arrangement placed elements with similar properties into horizontal rows.

The periodic table of chemical elements, often called the periodic table, organizes all discovered chemical elements in rows (called periods) and columns (called groups) according to increasing atomic ...

It can be possible to predict whether an atom will form a cation or an anion based on its position on the periodic table. Halogens always form anions, alkali metals and alkaline earth metals always ...

Today, the periodic table is organized by atomic number, which is the number of protons in the nucleus. But they didn’t know about protons then, so they organized everything by atomic weight.

The periodic table of elements—also known as Mendeleev’s table—was developed in 1869 by Russian chemist Dmitri Mendeleev. It organizes all known chemical elements by their atomic number, ...

The periodic table brought solidity to a field of inquiry that had long been squishy. Sir Isaac Newton, in Query 31, a section in his 1717 work “Opticks,” listed and ranked chemical compounds ...

An international team of scientists has shed light on the extreme ends of neutron and proton numbers. Their goal is to investigate the limits of the periodic table of chemical elements. How far ...

Elements 113, 115, 117 and 118 to be named by scientists from Russia, the United States and Japan.

All matter–oceans, land, atmosphere, humans, animals, plants, food, materials, products, buildings–is made from 118 known chemical elements. These elements are ordered in the periodic table of ...

At the American Chemical Society (ACS), our vision is to improve people's lives through the transforming power of chemistry. Next year marks the 150th anniversary of the publication of Mendeleev's ...

It can be possible to predict whether an atom will form a cation or an anion based on its position on the periodic table. Halogens always form anions, alkali metals and alkaline earth metals always ...