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.
CERN: physicists report the discovery of unique...
on July 9, 2020 at 2:32 pm
The LHCb collaboration at CERN has announced the discovery of a new exotic particle: a so-called "tetraquark". The paper by more than 800 authors is yet to be evaluated by other scientists in a process called "peer review", but has been presented at a seminar. It also meets the usual statistical threshold for claiming the discovery of a new particle.
Bright early light of LEDs
on July 8, 2020 at 5:25 pm
LED lamps are lighting up the world more and more. Global LED sales in residential lighting have risen from five percent of the market in 2013 to 40 percent in 2018, according to the International Energy Agency, and other sectors mirror these trends. An unmatched energy efficiency and sturdiness have made LED lights popular with consumers.
Learning more about particle collisions with...
on July 8, 2020 at 4:58 pm
The Large Hadron Collider (LHC) near Geneva, Switzerland became famous around the world in 2012 with the detection of the Higgs boson. The observation marked a crucial confirmation of the Standard Model of particle physics, which organizes the subatomic particles into groups similar to elements in the periodic table from chemistry.
Elucidating how asymmetry confers chemical...
on July 1, 2020 at 4:43 pm
You've heard the expression 'form follows function'? In materials science, function follows form.
Researchers discover new boron-lanthanide...
on June 25, 2020 at 7:15 pm
The discovery of carbon nanostructures like two-dimensional graphene and soccer ball-shaped buckyballs helped to launch a nanotechnology revolution. In recent years, researchers from Brown University and elsewhere have shown that boron, carbon's neighbor on the periodic table, can make interesting nanostructures too, including two-dimensional borophene and a buckyball-like hollow cage structure called borospherene.
Introducing a new isotope: Mendelevium-244
on June 23, 2020 at 8:36 pm
A team of scientists working at Lawrence Berkeley National Laboratory (Berkeley Lab) has discovered a new form of the human-made element mendelevium. The newly created isotope, mendelevium-244, is the 17th and lightest form of mendelevium, which is element 101 on the periodic table.
Scientists discover a long-sought-after nitrogen...
on June 16, 2020 at 3:11 pm
Graphene, or a single layer of graphite, has a set of novel properties that have attracted tremendous attention since its discovery. Nitrogen is the next neighbor to carbon in the periodic table of elements, so it is natural to question whether nitrogen can form a 2-D material similar to graphene. It is not easy to imagine such a nitrogen layer because nitrogen has one more electron than carbon, overwhelming the bonding requirement of graphene. However, all elements in the VA group bar nitrogen […]
Cuba's clean rivers show the benefits of reducing...
on June 10, 2020 at 2:20 pm
For most of the past 60 years, the United States and Cuba have had very limited diplomatic ties. President Barack Obama started the process of normalizing U.S.-Cuba relations, but the Trump administration reversed this policy, sharply reducing interactions between the two countries.
New material allows for unprecedented imaging...
on June 9, 2020 at 4:48 pm
A team from the Department of Chemistry has established an approach for the creation of a metal-organic framework material that provides new perspectives for the sensitization of near-infrared luminescent lanthanide ions, including unprecedented possibilities of imaging deeper in tissues for more comprehensive studies of biological systems with light.
Orbital ordering triggers nucleation-growth...
on June 1, 2020 at 2:23 pm
A new study by researchers from Waseda University and the University of Tokyo found that orbital ordering in a vanadate compound exhibits a clear nucleation-growth behavior.