What is Anion (Negative ions)?

Anion

“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.”

Anion and Health

All living things in the world are related to ‘anions’ (or negative ions). Do you know anions? Under normal circumstances, the air molecules or atoms are neutral. Due to natural ionization caused by cosmic rays, ultraviolet rays, micro radiation, lightning and thunder etc, some air molecules will lose some electrons that were orbiting around the nucleus and these free electrons with negative charge will combine with other neutral air molecules to make them negatively charged. These are the negative ions in the air. They are colourless, odorless and have strong absorption capability to absorb micro particles in the air to remove dust and bacteria. Anions in the air are as important as vitamins in the food and are given such nice names as ‘air vitamin’, ‘longevity element’, ‘air scavenger’ etc.

Anions (negative ion) have special significance to human health. Their effects should not be underestimated. They can have extraordinary absorption capability to gather the dust particles, bacteria and virus which are normally of positive charge and neutralize them. They can enter the cells of the bacteria to kill off the bacteria. More anions in the air would mean fewer bacteria and when the concentration of anions reaches a certain level, the number of bacteria would be reduced to zero.

The number of anions in a cubic centimeter (cc) of air is 40 to 50 in the urban residential area, 100 to 200 above the urban area, 700 to 1,000 in the field and more than 5,000 in the valley. The number of anions in the air can impact on human health. If the air has too high a content of positive ions and too few anions, then the human body may develop symptoms such as fatigue, dizziness, migraine, depression and shortness of breath, but these could be rapidly relieved if air with 1,200 anions per cc is taken in by the body. If the anion content of indoor air is raised to 1,500 per cc, it can improve the mood of those who stay in the room so that they can work better with higher efficiency. Therefore, anion content is an essential factor for human health and longevity.

The World Health Organization (WHO) has specified that the anion content in the air should not be lower than 1,000 per cc. In certain types of environment (such as the mountainous area), the inhabitants are free from troubles of inflammation and generally live longer. This is obviously related to the fact that the air there contains abundant anions.

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