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oxidation and reduction

(Encyclopedia)oxidation 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 was used to re...

reduction

(Encyclopedia)reduction, in chemistry: see oxidation and reduction. ...

oxidation number

(Encyclopedia)oxidation number or oxidation state: see valence. ...

redox

(Encyclopedia)redox rēˈdŏks [key]: see oxidation and reduction. ...

electromotive series

(Encyclopedia)electromotive series, list of metals whose order indicates the relative tendency to be oxidized, or to give up electrons (see oxidation and reduction); the list also includes the gas hydrogen. The ele...

fuel cell

(Encyclopedia)fuel cell, electric cell in which the chemical energy from the oxidation of a gas fuel is converted directly to electrical energy in a continuous process (see oxidation and reduction). The efficiency ...

valence, in chemistry

(Encyclopedia)valence, combining capacity of an atom expressed as the number of single bonds the atom can form or the number of electrons an element gives up or accepts when reacting to form a compound. Atoms are c...

oxidases

(Encyclopedia)oxidases, in biochemistry, enzymes that catalyze reactions that directly involve molecular oxygen (see oxidation and reduction). Some utilize flavin coenzymes derived from riboflavin (see vitamin B2)....

anion

(Encyclopedia)anion ănˈīˌən [key], 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 reduc...

cation

(Encyclopedia)cation kătˌīˈən [key], 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 oxi...