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
Renewable Energy Made by Mixing Salt and Fresh Water
Sep 02, 2009 |
4.3 / 5 (27) |
6
(PhysOrg.com) -- When a river flows into the sea, the location is more than just a haven for water commerce. The mixing of fresh and salt water that occurs at an estuary also dissipates energy, as the different ...
Ion trap quantum computing
May 12, 2009 |
4.5 / 5 (11) |
1
(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 ...
Salt Water System Could Generate Hydrogen
Mar 18, 2009 |
3.9 / 5 (31) |
18
(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 ...
Nanochemistry in Action
Nanotechnology / Nanomaterials
Mar 06, 2009 |
3.8 / 5 (6) |
0
(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 ...
'Core-Shell' Silicon Nanowires May Improve Lithium-Ion Batteries
Jan 20, 2009 |
4 / 5 (12) |
9
(PhysOrg.com) -- Researchers have found a way to incorporate silicon into the structure of rechargeable lithium-ion batteries, which are used to power a wide variety of portable electronic devices, including ...
Smart drug delivery system -- Gold nanocage covered with polymer (w/ Video)
Nov 01, 2009 |
5 / 5 (5) |
0
In campy old movies, Lucretia Borgia swans around emptying powder from her ring into wine glasses carelessly left unattended. The poison ring is usually a confection of gold filigree holding a cabochon or ...
Salt and Paper Battery May One Day Replace Lithium Batteries
Sep 15, 2009 |
4.5 / 5 (17) |
6
(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 ...
Wastewater produces electricity and desalinates water
Aug 06, 2009 |
4.5 / 5 (16) |
1
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.
Physicists demonstrate quantum entanglement in mechanical system
Jun 03, 2009 |
4.8 / 5 (14) |
3
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 ...
Flow of potassium into cells implicated in schizophrenia
May 06, 2009 |
5 / 5 (8) |
2
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 ...
Power thrust for spider silk
Apr 24, 2009 |
4 / 5 (11) |
2
(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 ...
Chameleon-like camouflage: 'Nano-camo' for fashionistas and environmentalists
Nanotechnology / Nanomaterials
Apr 17, 2009 |
4 / 5 (10) |
1
(PhysOrg.com) -- Certain fish species blend with their environment by changing color. Sandia National Laboratories researchers have demonstrated that, in theory, they could cause synthetic materials to change ...
Alzheimer’s Findings Resolve Dispute Over How Disease Kills Brain Cells
Medicine & Health / Neuroscience
Apr 15, 2009 |
4.2 / 5 (6) |
0
(PhysOrg.com) -- For a decade, Alzheimer's disease researchers have been entrenched in debate about one of the mechanisms believed to be responsible for brain cell death and memory loss in the illness.
A Pocketful of Uranium: Construction of a Selective Uranium-Binding Protein
Feb 12, 2009 |
4 / 5 (6) |
1
(PhysOrg.com) -- The use of uranium as a nuclear fuel and in weapons increases the risk that people may come into contact with it, and the storage of radioactive uranium waste poses an additional environmental risk. However, ...
New research may lead to new ways to control honeybee parasite
Dec 08, 2009 |
4.5 / 5 (4) |
0
(PhysOrg.com) -- Ground-breaking discoveries by Michigan State University researchers could help protect honeybees from deadly parasites that have devastated commercial colonies.
