What does oxidation number mean?

Definitions for oxidation number
ox·i·da·tion num·ber

This dictionary definitions page includes all the possible meanings, example usage and translations of the word oxidation number.

Princeton's WordNet

  1. oxidation number, oxidation statenoun

    the degree of oxidation of an atom or ion or molecule; for simple atoms or ions the oxidation number is equal to the ionic charge

    "the oxidation number of hydrogen is +1 and of oxygen is -2"


  1. oxidation numbernoun

    The net sum of the negative, less the positive, charges on an atom.


  1. oxidation number

    In chemistry, the oxidation state, or oxidation number, is the hypothetical charge of an atom if all of its bonds to different atoms were fully ionic. It describes the degree of oxidation (loss of electrons) of an atom in a chemical compound. Conceptually, the oxidation state may be positive, negative or zero. While fully ionic bonds are not found in nature, many bonds exhibit strong ionicity, making oxidation state a useful predictor of charge. The oxidation state of an atom does not represent the "real" charge on that atom, or any other actual atomic property. This is particularly true of high oxidation states, where the ionization energy required to produce a multiply positive ion is far greater than the energies available in chemical reactions. Additionally, the oxidation states of atoms in a given compound may vary depending on the choice of electronegativity scale used in their calculation. Thus, the oxidation state of an atom in a compound is purely a formalism. It is nevertheless important in understanding the nomenclature conventions of inorganic compounds. Also, several observations regarding chemical reactions may be explained at a basic level in terms of oxidation states. Oxidation states are typically represented by integers which may be positive, zero, or negative. In some cases, the average oxidation state of an element is a fraction, such as 8/3 for iron in magnetite Fe3O4 (see below). The highest known oxidation state is reported to be +9, displayed by iridium in the tetroxoiridium(IX) cation (IrO+4). It is predicted that even a +10 oxidation state may be achieved by platinum in tetroxoplatinum(X), PtO2+4. The lowest oxidation state is −5, as for boron in Al3BC.In inorganic nomenclature, the oxidation state is represented by a Roman numeral placed after the element name inside parentheses or as a superscript after the element symbol, e.g. Iron(III) oxide. The term oxidation was first used by Antoine Lavoisier to signify the reaction of a substance with oxygen. Much later, it was realized that the substance, upon being oxidized, loses electrons, and the meaning was extended to include other reactions in which electrons are lost, regardless of whether oxygen was involved. The increase in the oxidation state of an atom, through a chemical reaction, is known as oxidation; a decrease in oxidation state is known as a reduction. Such reactions involve the formal transfer of electrons: a net gain in electrons being a reduction, and a net loss of electrons being oxidation. For pure elements, the oxidation state is zero.


  1. oxidation number

    The oxidation number, also known as oxidation state, is a measure of the degree of oxidation (loss of electrons) of an atom in a chemical compound. It can be positive, negative or zero, representing the hypothetical charge that an atom would have if all bonds to atoms of different elements were 100% ionic. Conceptually, the oxidation state is defined as the number of valence electrons that an atom can lose, gain, or share when chemically bonding with another atom.


  1. Oxidation number

    Oxidation number is used in the nomenclature of inorganic compounds where it is represented by a Roman numeral. In older literature the term is referred to as Stock number, however the use of this term is no longer recommended. Oxidation number represents the degree of oxidation of an element in a substance. This degree of oxidation is, with the exception of coordination compounds where a different definition applies, the imaginary charge on the atom if the substance were broken down into ions. The oxidation number in compound naming is placed either as a right superscript to the element symbol in chemical formula, for example FeIII, or in parentheses after the name of the element, iron in chemical names. For example Fe2(SO4)3 would be named iron sulfate and its formula could be shown as FeIII2(SO4)3. This is because a sulfate ion has a charge of -2, so each iron atom takes a charge of +3. Note that fractional oxidation numbers should not be used in naming. In coordination chemistry, the oxidation number of a coordination compound is the charge that the central atom would possess if all the ligands were removed along with the electron pairs that were shared with the central atom.

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How to say oxidation number in sign language?


  1. Chaldean Numerology

    The numerical value of oxidation number in Chaldean Numerology is: 5

  2. Pythagorean Numerology

    The numerical value of oxidation number in Pythagorean Numerology is: 4

Translations for oxidation number

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"oxidation number." Definitions.net. STANDS4 LLC, 2023. Web. 29 Nov. 2023. <https://www.definitions.net/definition/oxidation+number>.

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