Periodic Table of Elements (International Union of Pure and Applied Chemistry)
Interactive Periodic Table of Elements (Los Alamos National Laboratory)
Periodic Table (American Chemical Society)
These are organized by a classification scheme developed exclusively for Cosma. More…
Periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties, whose structure shows periodic trends. Generally, within one row (period) the elements are metals to the left, and non-metals to the right, with the elements having similar chemical behaviours placed in the same column. Table rows are commonly called periods and columns are called groups. Six groups have accepted names as well as assigned numbers: for example, group 17 elements are the halogens; and group 18 are the noble gases. Also displayed are four simple rectangular areas or blocks associated with the filling of different atomic orbitals.
The organization of the periodic table can be used to derive relationships between the various element properties, but also the predicted chemical properties and behaviours of undiscovered or newly synthesized elements. Russian chemist Dmitri Mendeleev was the first to publish a recognizable periodic table in 1869, developed mainly to illustrate periodic trends of the then-known elements. He also predicted some properties of unidentified elements that were expected to fill gaps within the table. Most of his forecasts proved to be correct. Mendeleev’s idea has been slowly expanded and refined with the discovery or synthesis of further new elements and the development of new theoretical models to explain chemical behaviour. The modern periodic table now provides a useful framework for analyzing chemical reactions, and continues to be widely used in chemistry, nuclear physics and other sciences.
All the elements from atomic numbers 1 (hydrogen) through 118 (oganesson) have been either discovered or synthesized, completing the first seven rows of the periodic table. The first 98 elements exist in nature, although some are found only in trace amounts and others were synthesized in laboratories before being found in nature. Elements 99 to 118 have only been synthesized in laboratories or nuclear reactors. The synthesis of elements having higher atomic numbers is currently being pursued: these elements would begin an eighth row, and theoretical work has been done to suggest possible candidates for this extension. Numerous synthetic radionuclides of naturally occurring elements have also been produced in laboratories. — Wikipedia
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Crystal with a twist: scientists grow spiraling...
on June 20, 2019 at 11:43 am
With a simple twist of the fingers, one can create a beautiful spiral from a deck of cards. In the same way, scientists at the University of California, Berkeley, and Lawrence Berkeley National Laboratory (Berkeley Lab) have created new inorganic crystals made of stacks of atomically thin sheets that unexpectedly spiral like a nanoscale card deck. […]
Collaborative research charts course to hundreds...
on June 18, 2019 at 12:11 pm
Andriy Zakutayev knows the odds of a scientist stumbling across a new nitride mineral are about the same as a ship happening upon a previously undiscovered landmass. […]
The hidden structure of the periodic system
on June 17, 2019 at 11:26 am
The periodic table of elements that most chemistry books depict is only one special case. This tabular overview of the chemical elements, which goes back to Dmitri Mendeleev and Lothar Meyer and the approaches of other chemists to organize the elements, involve different forms of representation of a hidden structure of the chemical elements. This is the conclusion reached by researchers at the Max Planck Institute for Mathematics in the Sciences in Leipzig and the University of Leipzig in a […]
Earth's heavy metals result of supernova explosion
on June 13, 2019 at 4:35 pm
That gold on your ring finger is stellar—and not just in a complimentary way. […]
Engineers use graph networks to accurately...
on June 10, 2019 at 2:23 pm
Nanoengineers at the University of California San Diego have developed new deep learning models that can accurately predict the properties of molecules and crystals. By enabling almost instantaneous property predictions, these deep learning models provide researchers the means to rapidly scan the nearly-infinite universe of compounds to discover potentially transformative materials for various technological applications, such as high-energy-density Li-ion batteries, warm-white LEDs, and better […]
Direct observation of giant molecules
on June 6, 2019 at 11:44 am
Physicists at the Max Planck Institute for Quantum Optics (MPQ) achieved to form giant diatomic molecules and optically detect them afterwards by using a high-resolution objective. […]
Separation anxiety no more: A faster technique to...
on June 4, 2019 at 9:32 am
The actinides—those chemical elements on the bottom row of the periodic table—are used in applications ranging from medical treatments to space exploration to nuclear energy production. But purifying the target element so it can be used, by separating out contaminants and other elements, can be difficult and time-consuming. […]
Floating cities: The future or a washed-up idea?
on June 3, 2019 at 1:30 pm
Humans have a long history of living on water. Our water homes span the fishing villages in Southeast Asia, Peru and Bolivia to modern floating homes in Vancouver and Amsterdam. As our cities grapple with overcrowding and undesirable living situations, the ocean remains a potential frontier for sophisticated water-based communities. […]
Finding a needle in a haystack: Discovery of...
on June 3, 2019 at 12:20 pm
Scientists at Tokyo Institute of Technology (Tokyo Tech) have used boron as the X element in a family of materials called MAX phases, for which only carbon and nitrogen could previously be used. A clever search strategy allowed them to avoid resorting to trial and error to design this novel material, from which layered TiB can be obtained for applications in Li- or Na-ion batteries. […]
Scientists offer designer 'big atoms' on demand
on May 29, 2019 at 5:00 pm
In the not-so-distant future, researchers may be able to build atoms to your specifications with the click of a button. It's still the stuff of science fiction, but a team at the University of Colorado Boulder reports that it is getting closer when it comes to controlling and assembling particles called "big atoms." […]