WordNet

a substance that oxidizes another substance (同)oxidizer, oxidiser, oxidizing_agent
a substance that exerts some force or effect
a businessman who buys or sells for another in exchange for a commission (同)factor, broker
any agent or representative of a federal agency or bureau (同)federal agent
a representative who acts on behalf of other persons or organizations
an active and efficient cause; capable of producing a certain effect; "their research uncovered new disease agents"
how long something has existed; "it was replaced because of its age"
a time of life (usually defined in years) at which some particular qualification or power arises; "she was now of school age"; "tall for his eld" (同)eld
begin to seem older; get older; "The death of his wife caused him to age fast"
make older; "The death of his child aged him tremendously"

PrepTutorEJDIC

オキシダント,酸化体
『代理人』;周旋人 / 働き(作用)を起こすもの;作用物,薬剤 / (政府機関,特にFBI,CIAなどの)部員,機関員
〈U〉(一般に)『年齢』,寿命;〈C〉(個々の)『年齢』,年 / 〈U〉成年(おとなとしての資格・権利を得る年齢;通例18または21歳) / 〈U〉『老齢』;《集合的に》老人たち / 〈U〉(人生の)『一時期』;〈C〉世代(generation) / 〈U〉〈C〉《しばしばA-》(歴史上の)『時代』 / 〈C〉《話》長い間 / 年をとる,ふける;〈物が〉古くなる / 〈年〉'を'とらせる;〈物〉'を'古びさせる

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出典(authority):フリー百科事典『ウィキペディア（Wikipedia）』「2015/06/25 14:34:02」(JST)

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The international pictogram for oxidising chemicals.

Dangerous goods label for oxidising agents

An oxidizing agent (also oxidant, oxidizer or oxidiser) is the element or compound in an oxidation-reduction (redox) reaction that accepts an electron from another species. Because the oxidizing agent is gaining electrons (and is thus often called an electron acceptor), it is said to have been reduced.

The oxidizing agent itself is reduced, as it is taking electrons onto itself, but the reactant is oxidized by having its electrons taken away by the oxidizing agent. Oxygen is the prime (and eponymous) example among the varied types of oxidizing agents, but oxidisers (e.g., chlorine trifluoride) do not necessarily donate or contain oxygen.

Overview

The oxidizing agent takes electrons from another species, and thus itself is reduced.
The reducing agent gives electrons to another species, and thus itself is oxidized.
All atoms in a molecule can be assigned an oxidation number. This number changes when an oxidant acts on a substrate.
Redox reactions occur when oxidation states of the reactants change.

Example of oxidation

Rust and dirt on a baking plate.

The formation of iron(III) oxide (rust) through the oxidation of iron;

4Fe + 3O₂ → 2Fe₂O₃

In the above equation, the iron (Fe) has an oxidation number of 0 before and 3+ after the reaction. For oxygen (O) the oxidation number began as 0 and decreased to 2−. These changes can be viewed as two (balanced) "half-reactions" that occur concurrently:

Oxidation half reaction: 4Fe → 4Fe³⁺ + 12e⁻
Reduction half reaction: 3O₂ + 12e⁻ → 6O²⁻

Iron (Fe) has become oxidised because its oxidation number increased and was the reducing agent because it gave electrons to the oxygen (O). Oxygen (O) has been reduced because the oxidation number has decreased and was the oxidising agent because it took electrons from iron (Fe).

Electron acceptor

Because the process of oxidation is so widespread (fire, explosives, chemical synthesis, corrosion), the term oxidising agent has acquired multiple meanings.

In one definition, an oxidising agent accepts - or gains - electrons. In this context, the oxidizing agent is called an electron acceptor and the reducing agent is called an electron donor. A classic oxidising agent is the ferrocenium ion [Fe(C₅H₅)₂]⁺, which accepts an electron to form Fe(C₅H₅)₂. Of great interest to chemists are the details of the electron transfer event, which can be described as inner sphere or outer sphere.

In more colloquial usage, an oxidising agent transfers oxygen atoms to the substrate. In this context, the oxidising agent can be called an oxygenation reagent or oxygen-atom transfer agent. Examples include [MnO₄]⁻ (permanganate), [CrO₄]²⁻ (chromate), OsO₄ (osmium tetroxide), and especially [ClO₄]⁻ (perchlorate). Notice that these species are all oxides, and are in fact polyoxides. In some cases, these oxides can also serve as electron acceptors, as illustrated by the conversion of [MnO₄]⁻ to [MnO₄]²⁻, manganate.

Dangerous materials definition

The dangerous materials definition of an oxidizing agent is a substance that is not necessarily combustible, but may, generally by yielding oxygen, cause or contribute to the combustion of other material.^[1] By this definition some materials that are classified as oxidising agents by analytical chemists are not classified as oxidising agents in a dangerous materials sense. An example is potassium dichromate, which does not pass the dangerous goods test of an oxidising agent.

The U.S. Department of Transportation defines Oxidizing agent specifically. There are two definitions for oxidizing agents governed under DOT regulations. These two are Class 5; Division 5.1 and Class 5; Division 5.2. Division 5.1 "means a material that may, generally by yielding oxygen, cause or enhance the combustion of other materials." Division 5.1 of the DOT code applies to solid oxidizers "if, when tested in accordance with the UN Manual of Tests and Criteria (IBR, see § 171.7 of this subchapter), its mean burning time is less than or equal to the burning time of a 3:7 potassium bromate/cellulose mixture." 5.1 of the DOT code applies to liquid oxidizers "if, when tested in accordance with the UN Manual of Tests and Criteria, it spontaneously ignites or its mean time for a pressure rise from 690 kPa to 2070 kPa gauge is less than the time of a 1:1 nitric acid (65 percent)/cellulose mixture."^[2]

Common oxidizing agents

Oxygen (O₂)
Ozone (O₃)
Hydrogen peroxide (H₂O₂) and other inorganic peroxides
Fluorine (F₂), chlorine (Cl₂), and other halogens
Nitric acid (HNO₃) and nitrate compounds
Sulfuric acid (H₂SO₄)
Peroxydisulfuric acid (H₂S₂O₈)
Peroxymonosulfuric acid (H₂SO₅)
Chlorite, chlorate, perchlorate, and other analogous halogen compounds
Hypochlorite and other hypohalite compounds, including household bleach (NaClO)
Hexavalent chromium compounds such as chromic and dichromic acids and chromium trioxide, pyridinium chlorochromate (PCC), and chromate/dichromate compounds
Permanganate compounds such as potassium permanganate
Sodium perborate
Nitrous oxide (N₂O)
Silver oxide (Ag₂O)
Osmium tetroxide (OsO₄)
Potassium nitrate (KNO₃), the oxidizer in black powder
Tollens' reagent
2,2'-Dipyridyldisulfide (DPS)

Common oxidizing agents and their products

Agent	Product(s)
O₂ oxygen	Various, including the oxides H₂O and CO₂
O₃ ozone	Various, including ketones, aldehydes, and H₂O; see ozonolysis
F₂ fluorine	F⁻
Cl₂ chlorine	Cl⁻
Br₂ bromine	Br⁻
I₂ iodine	I⁻, I₃⁻
ClO⁻ hypochlorite	Cl⁻, H₂O
ClO₃⁻ chlorate	Cl⁻, H₂O
HNO₃ nitric acid	NO nitric oxide NO₂ nitrogen dioxide
Hexavalent chromium CrO₃ chromium trioxide CrO₄²⁻ chromate Cr₂O₇²⁻ dichromate	Cr³⁺, H₂O
MnO₄⁻ permanganate MnO₄²⁻ manganate	Mn²⁺ (acidic) or MnO₂ (basic)
H₂O₂, other peroxides	Various, including oxides and H₂O

References

^ Australian Dangerous Goods Code, 6th Edition
^ 49 CFR 172.127 General Requirements for Shipments and Packagings; Subpart D

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English Journal

Kinetics of protein physicochemical changes induced by heating in meat using mimetic models: (1) Relative effects of heat and oxidants.

Promeyrat A, Daudin JD, Gatellier P.SourceINRA, UR370 Qualité des Produits Animaux, F-63122 Saint-Genès-Champanelle, France.
Food chemistry.Food Chem.2013 May 1;138(1):581-9. doi: 10.1016/j.foodchem.2012.10.084. Epub 2012 Nov 10.
Optimizing the nutritional quality of cooked meat needs a better understanding of the mechanisms responsible for protein changes induced by heating. The relative contributions of chemical and thermal effects on protein physicochemical changes were studied using meat models. Two models were tested: a
PMID 23265527

Fast method for multielemental analysis of plants and discrimination according to the anatomical part by total reflection X-ray fluorescence spectrometry.

De La Calle I, Costas M, Cabaleiro N, Lavilla I, Bendicho C.SourceDepartamento de Química Analítica y Alimentaria, Área de Química Analítica, Facultad de Química, Universidad de Vigo, Campus As Lagoas-Marcosende s/n, 36310 Vigo, Spain.
Food chemistry.Food Chem.2013 May 1;138(1):234-41. doi: 10.1016/j.foodchem.2012.09.105. Epub 2012 Nov 8.
Fast and reliable analytical methodologies are required for quality control of plants in order to assure human health. Ultrasound-assisted extraction in combination with total reflection X-ray fluorescence is proposed as a fast and simple method for multielemental analysis of plants on a routine bas
PMID 23265482

Differential oxidative stress induction and lethality of rat embryos after maternal exposure to t-butyl hydroperoxide during postimplantation period.

Shivananjappa MM, Muralidhara.SourceDepartment of Biochemistry and Nutrition, Central Food Technological Research Institute , Mysore, Karnataka , India.
Drug and chemical toxicology.Drug Chem Toxicol.2013 Apr;39(2):209-16. doi: 10.3109/01480545.2012.710622. Epub 2012 Sep 5.
In mammals, reactive oxygen species (ROS) are essential factors for cell proliferation, differentiation, and growth, notably during gestation, but are also potentially damaging agents. The present study describes the extent and pattern of oxidative stress (OS) induction in maternal milieu, placenta,
PMID 22947016

Japanese Journal

Partial oxidation of alcohols with O2 catalyzed by Ru0/Al2O3

, ,
Chemistry Letters advpub(0), 2015
… Partial oxidation of alcohols was performed over Ru/Al2O3 using O2 as the oxidizing agent. …
NAID 130005071120

Nitrous Oxide Emissions from Dairy Manure Compost

Japan Agricultural Research Quarterly: JARQ 49(1), 17-21, 2015
… Both pile-turning events and inappropriate use of mature compost containing NOx--N may cause N2O emissions to soar, although using bulking agent appropriately can also reduce them significantly. … Significant NOx--N is accumulated in the pile surface between the pile turnings, and β-proteobacterial ammonia-oxidizing bacteria is seemingly the main contributor to this accumulation. …
NAID 130004886286

γ-Al2O3とMnO2によるAs(III)の酸化吸着挙動

吉井功至,小谷拓哉,村山憲弘 [他],芝田隼次
化学工学論文集 40(3), 250-254, 2014
世界の各地で地下水のヒ素汚染が環境上の問題となっている．地下水中のヒ素は亜ヒ酸（As(III)）およびヒ酸（As(V)）として存在する．本研究では，ヒ素の吸着剤としてγ-Al2O3を用いて，As(III)/As(V)混合水溶液からのAs(III)とAs(V)の競争吸着について検討した．As(III)の除去性能を向上させるために，MnO2によるAs(III)の酸化作用を検討した．γ-Al2O3にMn …
NAID 130004855776