The rare radioactive substance made its way from the United States to Russia on a commercial flight in June 2009. Customs officers balked at accepting the package, which was ensconced in lead ...

On the periodic table, most elements have at least one stable form. But others have only unstable forms, all of which decay by emitting radiation and transforming into different elements until ...

Since element 99 -- einsteinium -- was discovered in 1952 from the debris of the first hydrogen bomb, scientists have performed very few experiments with it because it is so hard to create and is ...

As the Class 10th Science board exam nears, students all over the country are always in a time race to cement their grasp on the basic concepts, with the foremost being the periodic table. This is the ...

A century and a half ago, a Russian chemistry professor published a classification of all the known elements, organized by atomic weight. Today, the system that he created for his students — plus some ...

At the middle of the 19th century, 63 chemical elements were known to science. Before Mendeleev’s discovery, attempts at arranging them in some logical way were made by Johann Doebereiner (1829), ...

How is the table organized? The Periodic Table, first compiled by Russian chemist Dmitri Mendeleyev, is organized by the number of protons in the nucleus of each element's atom, known as the atomic ...