Ion
hideAn 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.
For more information about Ion, read the full article at
Wikipedia.
This text uses material from Wikipedia and is available under the GNU Free Documentation License.
News tagged with ions
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(PhysOrg.com) -- The idea of generating hydrogen from salt water has often been claimed to work effectively. However, the systems proposed so far generally require a much greater energy input than the energy ...
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(PhysOrg.com) -- Using a nanoparticle from corn, a Purdue University scientist has found a way to lengthen the shelf life of many food products and sustain their health benefits.
Nanochemistry in Action
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(PhysOrg.com) -- Using a single-walled carbon nanotube (SWCNT) as a test tube, scientists can explore chemistry at the nanoscale, which involves some unique effects. Nanotubes provide a confined, one-dimensional ...
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(PhysOrg.com) -- “Right now, classical computers are faster than quantum computers,” René Stock tells PhysOrg.com. “The goal of quantum computing is to eventually speed up the time scale of solving certain important proble ...
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(PhysOrg.com) -- Salt and paper battery can be used in many low-power devices, such as medical implants, RFID tags, wireless sensors and smart cards. This battery uses a thin-film which makes it an attractive ...
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A process that cleans wastewater and generates electricity can also remove 90 percent of salt from brackish water or seawater, according to an international team of researchers from China and the U.S.
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Physicists at the National Institute of Standards and Technology have demonstrated entanglement--a phenomenon peculiar to the atomic-scale quantum world--in a mechanical system similar to those in the macroscopic ...
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(PhysOrg.com) -- Spiderman would definitely have an easier time of things with this spider silk - for example, if he had to stop a getaway car moving off at 100 kilometres per hour. A five-millimetre-thick ...
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In the quest to produce nuclear fusion energy, researchers from the DIII-D National Fusion Facility have recently confirmed long-standing theoretical predictions that performance, efficiency and reliability ...
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A study on schizophrenia has implicated machinery that maintains the flow of potassium in cells and revealed a potential molecular target for new treatments. Expression of a previously unknown form of a key ...


