Seeking a treatment for IBS pain in tarantula venom

For patients who have inflammatory bowel syndrome (IBS), the condition is literally a pain in the gut. Chronic—or long-term—abdominal pain is common, and there are currently no effective treatment options for this debilitating ...

Using starch and baking soda to harvest mechanical energy

Scientists have used a compound made from a starch derivative and baking soda to help convert mechanical energy to electrical energy. The approach, developed by scientists at Daegu Gyeongbuk Institute of Technology (DGIST), ...

A colorful look at fast-flying particles

The strong nuclear force is one of the four fundamental forces of nature, along with the electromagnetic, gravitational and weak nuclear forces. The branch of particle physics that deals with the strong nuclear force is called ...

Graphene drum: A new phonon laser design

Professor Konstantin Arutyunov of the HSE Tikhonov Moscow Institute of Electronics and Mathematics (MIEM HSE), together with Chinese researchers, has developed a graphene-based mechanical resonator, in which coherent emission ...

Juno detects Jupiter's highest-energy ions

Jupiter's planetary radiation environment is the most intense in the solar system. NASA's Juno spacecraft has been orbiting the planet closer than any previous mission since 2016, investigating its innermost radiation belts ...

Insulators turn up the heat on quantum bits

Physicists have long suspected that dielectric materials may significantly disrupt ion-trap quantum computers. Now, researchers led by Tracy Northup have developed a new method to quantify this source of error for the first ...

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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