Optical wiring for large quantum computers

Researchers at ETH have demonstrated a new technique for carrying out sensitive quantum operations on atoms. In this technique, the control laser light is delivered directly inside a chip. This should make it possible to ...

Oxygen can do a favor to synthesize metal-organic frameworks

Metal-organic frameworks, or MOFs, are composed of metal ions periodically surrounded by organic bridging molecules, and these hybrid crystalline frameworks feature a cage-like hollow structure. This unique structure motif ...

Computational study reveals how Ebola nucleocapsid stabilizes

The Ebola virus causes a serious infection with a mortality rate between 50% and 90%. Nucleoproteins in the virus assemble into a helical arrangement and encapsulate a single stranded RNA genome, ssRNA, to form a rodlike ...

Calcium bursts kill drug-resistant tumor cells

Multidrug resistance (MDR)—a process in which tumors become resistant to multiple medicines—is the main cause of failure of cancer chemotherapy. Tumor cells often acquire MDR by boosting their production of proteins that ...

Nanomaterial acts as a molecular thermometer

A layered material developed by KAUST researchers can act as a precise temperature sensor by exploiting the same principle used in biological ion channels.

Researchers probe memory of the Venus flytrap

The carnivorous plant Venus flytrap (Dionaea muscipula) captures and digests small animals and absorbs nutrients with its characteristic insectivorous leaves. Six sensory hairs on the inner surface of each leaf sense a visiting ...

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Ion

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