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Related to anion: anion exchange, anion gap
anion(ăn`ī'ən), atom or group of atoms carrying a negative charge. The charge results because there are more electrons than protons in the anion. Anions can be formed from nonmetals by reduction (see oxidation and reductionoxidation and reduction,
complementary chemical reactions characterized by the loss or gain, respectively, of one or more electrons by an atom or molecule. Originally the term oxidation
..... Click the link for more information. ) or from neutral acids (see acids and basesacids and bases,
two related classes of chemicals; the members of each class have a number of common properties when dissolved in a solvent, usually water. Properties
..... Click the link for more information. ) or polar compounds by ionization. Anionic species include Cl−, SO4−−, and CH3COO−. Highly colored intermediates in organic reactions are often radical anions (anions containing an unpaired electron). Saltssalt,
chemical compound (other than water) formed by a chemical reaction between an acid and a base (see acids and bases). Characteristics and Classification of Salts
The most familiar salt is sodium chloride, the principal component of common table salt.
..... Click the link for more information. are made up of anions and cationscation
, atom or group of atoms carrying a positive charge. The charge results because there are more protons than electrons in the cation. Cations can be formed from a metal by oxidation (see oxidation and reduction), from a neutral base (see acids and bases) by protonation, or
..... Click the link for more information. . See ionion,
atom or group of atoms having a net electric charge. Positive and Negative Electric Charges
A neutral atom or group of atoms becomes an ion by gaining or losing one or more electrons or protons.
..... Click the link for more information. .
An ion that is negatively charged.
a negatively charged ion; an ion that is attracted to the anode during electrolysis