A simplified method to categorize olive oil

Olive oil classification is currently very costly and slow. In order to categorize oil into extra virgin (EVOO), virgin (VOO) and lampante olive oil (LOO), an offical method is used, consisting of a physicochemical analysis ...

New coating could have big implications for lithium batteries

Building a better lithium-ion battery involves addressing a myriad of factors simultaneously, from keeping the battery's cathode electrically and ionically conductive to making sure that the battery stays safe after many ...

Electrode's 'hot edges' convert CO2 gas into fuels and chemicals

A team of scientists has created a bowl-shaped electrode with 'hot edges' which can efficiently convert CO2 from gas into carbon based fuels and chemicals, helping combat the climate change threat posed by atmospheric carbon ...

New method enables 'photographing' of enzymes

Scientists at the University of Bonn have developed a method with which an enzyme at work can be "photographed". Their method makes it possible to better understand the function of important biomolecules. The researchers ...

Recreating ancient minerals

When it comes to making a lasting impression in geological history, the medium makes all the difference, especially in the Earth's paleo-oceans. Here, during the Archean Eon (4,000-2,500 million years ago) and at times during ...

Assessing battery performance: Compared to what?

Scientists must often ask themselves, compared to what? How do the results we generate in the laboratory compare with those obtained by others? How do our theoretical calculations compare with experimental data?

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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