Surgery would be inconceivable without general anesthesia, so it may come as a surprise that despite its 175-year history of medical use, doctors and scientists have been unable to explain how anesthetics temporarily render ...
May 29, 2020
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Have you ever wondered why you feel healthier and happier when you stroll through the trees or frolic by the sea? Is it just that you're spending time away from work, de-stressing and taking in the view? Or is there more ...
Feb 1, 2016
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A team of researchers at Lund University in Sweden has developed a fluorescent variant of a molecule that inhibits cancer stem cells. Capturing images of the molecule entering a cell has enabled the researchers, using cell-biological ...
Jun 26, 2018
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A group of the Lomonosov Moscow State University scientists, together with their colleagues from the Institute of Molecular Biology, Russian Academy of Sciences and the King's College London, determined the mechanism of Alzheimer's ...
Mar 11, 2016
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Researchers at Tufts University School of Medicine have discovered a previously unknown function performed by a type of cell that comprises nearly half of all cells in the brain.
Apr 28, 2022
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Research led by Sanford Burnham Prebys professor Francesca Marassi, Ph.D., is helping to reveal the molecular secrets of macular degeneration, which causes almost 90% of all age-related vision loss. The study, published recently ...
Sep 7, 2022
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Researchers from Cornell University have identified a possible target for antiviral treatment for COVID-19.
Apr 7, 2020
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Researchers know that anxiety is a result of repeated stress. William Colmers, a University of Alberta professor in the Department of Pharmacology, is trying to understand why stress affects people differently, and to identify ...
Jun 14, 2018
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When a beating heart slips into an irregular, life-threatening rhythm, the treatment is well known: deliver a burst of electric current from a pacemaker or defibrillator. But because the electricity itself can cause pain, ...
Aug 28, 2013
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For decades, scientists have dreamed of building computer systems that could replicate the human brain’s talent for learning new tasks.
Nov 15, 2011
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An ion is an atom or molecule where the total number of electrons is not equal to the total number of protons, giving it a net positive or negative electrical charge.
Since protons are positively charged and electrons are negatively charged, if there are more electrons than protons, the atom or molecule will be negatively charged. This is called an anion (pronounced /ˈænaɪən/; an-eye-on), from the Greek ἀνά (ana), meaning 'up'.
Conversely, if there are more protons than electrons, the atom or molecule will be positively charged. This is called a cation (pronounced /ˈkætaɪən/; cat-eye-on), from the Greek κατά (kata), meaning 'down'.
An ion consisting of a single atom is called a monatomic ion. If it consists of two or more atoms, it is called a polyatomic ion. Polyatomic ions containing oxygen, such as carbonate and sulfate, are called oxyanions.
When writing the chemical formula for an ion, its charge is written as a superscript '+' or '−' following a number indicating the difference between the number of protons and the number of electrons. The number is omitted if it is equal to 1. For example, the sodium cation is written as Na+, the '+' indicating that it has one less electron than it has protons. The sulfate anion is written as SO42−, the '2−' indicating that it has two more electrons than it has protons.
If an ion contains unpaired electrons, it is called a radical ion. Just like neutral radicals, radical ions are very reactive.
This text uses material from Wikipedia, licensed under CC BY-SA
