We often learn something new from studying something old. More than 150 years before Mark Zuckerberg used the term the “social graph” to describe your network of connections on Facebook, a ...

Such questions exercised physicists greatly in the decades after Dmitri Mendeleev introduced his periodic table of the chemical elements in 1869. They received new impetus around the turn of the ...

Advertisement In 1869, chemist Dmitri Mendeleev introduced his concept of a periodic table of elements at a meeting of the Russian Chemical Society in St. Petersburg. In 1912, Oreo cookies were ...

An atom is so small that a single drop of water contains more than a billion atoms. Although tiny, atoms are mostly empty space. The simplified model of the atom is that of a cloud of negative ...

The periodic table - AQA Mendeleev made an early periodic table. In the modern periodic table, elements are in order of atomic number in periods and groups. Electronic structures model how ...

In 1869, Mendeleev's first periodic table did not include them, as closed-shell elements remained undiscovered until Lord Rayleigh and William Ramsey isolated argon in 1894. Remarkably ...

Because not all elements were then known, there were gaps in his periodic table, and Mendeleev successfully used the periodic law to predict the properties of some of the missing elements.

Heavy ligands such as polyoxometalates are opening a new frontier in actinide chemistry. Studying materials that are both ...

Or maybe you’ve spent hours manually formatting a table of contents, only to realize it’s outdated the moment you make a single edit? We’ve all been there, and it’s frustrating.

A young computer scientist and two colleagues show that searches within data structures called hash tables can be much faster ...