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
Phys.org - latest science and technology news stories Phys.org internet news portal provides the latest news on science including: Physics, Nanotechnology, Life Sciences, Space Science, Earth Science, Environment, Health and Medicine.
Stopping yellow spot fungus that attacks wheat...
on January 23, 2020 at 1:57 pm
Scientists from the Centre for Crop and Disease Management (CCDM) and Curtin University in Western Australia have used an advanced imaging technique at the Australian Synchrotron for an in-depth look at how a fungus found in wheat crops is damaging its leaves.
Making new catalysts from unique metallic alloys
on January 17, 2020 at 2:48 pm
Heusler alloys are magnetic materials made from three different metals that are not magnetic individually. The alloys are used broadly for their magnetic and thermoelectric properties, and their ability to regain their original shape after being deformed, known as shape memory. Investigations by Tohoku University's advanced materials scientist An-Pang Tsai and colleagues now show that these materials can also be fine-tuned to speed up chemical reactions. This catalytic capability is reviewed in […]
Potassium-driven rechargeable batteries: An...
on January 16, 2020 at 12:26 pm
Our modern lifestyle would be immensely different without rechargeable batteries. Owing to their low-cost, recyclable technology, these batteries are used in most portable electronic devices, electric and hybrid vehicles, and renewable power generation systems. They offer an elegant solution to the world's growing energy demands. Moreover, rechargeable batteries are an essential tool in systems that harvest renewable energy, such as the wind and sunlight, because these sources can fluctuate […]
Simulation of dwarf galaxy reveals different...
on January 10, 2020 at 12:40 pm
Simulations of a dwarf galaxy by RIKEN astrophysicists have revealed the various processes by which moderately heavy metals such as strontium are birthed. They have found that at least four kinds of stars are needed to explain the observed abundance of these metals in dwarf galaxies.
Technique to recover phosphorus from urine
on December 27, 2019 at 12:15 pm
Phosphorus, number 15 on the periodic table, can be highly toxic and flammable and has been used in warfare as an incendiary device, yet it is also essential for life.
These artificial proteins have a firm grasp on...
on December 23, 2019 at 11:03 am
A team of scientists led by Berkeley Lab has developed a library of artificial proteins or "peptoids" that effectively "chelate" or bind to lanthanides and actinides, heavy metals that make up the so-called f-block elements at the bottom of the periodic table.
New insights into the formation of Earth's crust
on December 19, 2019 at 8:21 am
New research from Mauricio Ibanez-Mejia, an assistant professor of Earth and environmental sciences at the University of Rochester, and Francois Tissot, an assistant professor of geochemistry at the California Institute of Technology, gives scientists better insight into the geological processes responsible for the formation of Earth's crust.
Researchers combine quantum dot 'atoms' and...
on December 16, 2019 at 3:53 pm
Are you ready for the future? Back in 1869, Russia's Dmitri Mendeleev began to classify the elements according to their chemical properties, giving rise to the Periodical Table of Elements. "I saw in a dream a table where all elements fell into place as required. Awakening, I immediately wrote it down on a piece of paper," Mendeleev recalled.
Study unveils new nonlinear dynamics of spinning...
on December 12, 2019 at 2:30 pm
Although researchers have been studying dark matter and trying to observe it, its nature is a longstanding scientific mystery. The standard cosmological model suggests that approximately one-quarter of cosmological energy and matter is almost immune to electromagnetic interactions, thus the only way to observe it is to study its gravitational effects. However, the type of particles that make up dark matter is still a subject of debate.
Stardust from red giants
on December 10, 2019 at 1:09 pm
Some of the Earth's building material was stardust from red giants, researchers from ETH Zurich have established. They have also explained why the Earth contains more of this stardust than the asteroids or the planet Mars, which are farther from the sun.