Electronics & Semiconductors
Optical technologies that can be used to modulate neuronal activity are opening up exciting possibilities for research in neuroscience and biology. Optical tools allow neuroscientists to excite and inhibit neurons or areas ...
Energy & Green Tech
Researchers of Karlsruhe Institute of Technology (KIT) and cooperating institutions studied structural changes during the synthesis of cathode materials for future high-energy lithium-ion batteries and obtained new major ...
Dec 10, 2019
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9
Engineering
From the moment you first use it, a new lithium-ion battery is degrading. After a few hundred charge cycles, you'll notice—your phone, laptop or electric car battery wears out more quickly. Eventually, it stops holding ...
Dec 22, 2022
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110
Energy & Green Tech
A step towards new "beyond lithium" rechargeable batteries with superior performance has been made by researchers at the University of Bath.
Sep 18, 2017
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38
Energy & Green Tech
The challenge of building an energy future that preserves and improves the planet is a massive undertaking. But it all hinges on the charged particles moving through invisibly small materials.
Nov 21, 2019
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212
Energy & Green Tech
A portfolio of 44 battery storage systems across San Diego County aimed at adding more emissions-free energy to California's electric grid is about to roll out, with one location in Chula Vista and another in El Cajon poised ...
Jan 5, 2022
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14
Energy & Green Tech
Researchers at the University of California, Riverside have created a new silicon-tin nanocomposite anode that could lead to lithium-ion batteries that can be charged and discharged more times before they reach the end of ...
Aug 3, 2016
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309
Energy & Green Tech
Scientists at UC San Diego have discovered a new anode material that enables lithium-ion batteries to be safely recharged within minutes for thousands of cycles. Known as a disordered rocksalt, the new anode is made up of ...
Sep 2, 2020
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83
Automotive
California firefighters ended up using a water-filled pit to douse stubborn flames in a Tesla's battery compartment earlier this month, illustrating the distinct difficulties in battling electric vehicle blazes.
Jun 30, 2022
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36
Engineering
A team of researchers from Tsinghua University and Northwest University, both in China, has developed a patch that can be used to measure six health-related biomarkers by analyzing sweat. In their paper published in the journal ...
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
