A to reduce agent (also called a reductant or reducer) is the element or a link in a redox (reduction-oxidation) reaction (see electrochemistry) the reduces one more species. In law so, it i do not care oxidized, and also is as such the electron donor in the redox. Because that example take into consideration the adhering to reaction:

4- + 1/2 Cl2 → 3- + Cl

The reducing certified dealer in this reaction is ferrocyanide: the donates one electron, converting to ferricyanide, simultaneous through the palliation of chlorine come chloride.

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In essential chemistry, reduction refers to the addition of hydrogen come a molecule. For example, benzene is reduced to cyclohexane in the existence of a platinum catalyst:

C6H6 + 3 H2 → C6H12

In necessary chemistry, good reducing agents space reagents that deliver H2.

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What makes a solid reducing agent?

Strong reduce agents quickly lose (or donate) electrons. Atoms through relatively large atomic radii have tendency to be better reductants. In together species, the street from the nucleus come the valence electron is so long that this electrons space not strong attracted. These aspects tend come be solid reducing agents. Good reducing agents often tend to covers atoms with a short electronegativity, the capability of one atom or molecule to tempt bonding electrons1, and reasonably small ionization energies offer as good reducing agents too. "The measure up of a material to oxidization or lose electrons is well-known as the oxidation potential"2. The table listed below shows a few reduction potentials that can easily be adjusted to oxidation potential by simply changing the sign. Reducing agents have the right to be ranked by raising strength by ranking your oxidation potentials. The reduce agent will be the strongest as soon as it has a an ext positive oxidation potential and also will be a weak reducing agent whenever it has actually a negative oxidation potential. The adhering to table offers the reduction potentials the the indicated reducing certified dealer at 25° C. Additionally remember the useful mnemonic devices, "OIL RIG," which method Oxidation Is ns (of electrons) and also Reduction Is gain (of electrons), or "LEO the lion claims GER," which way Loss of electron is Oxidation and also Gain of electron is Reduction.

Oxidizing AgentReducing AgentReduction Potential (v)
Li+ + e- =Li-3.04
Na+ + e- =Na-2.71
Mg2+ + 2e- =Mg-2.38
Al3+ + 3e- =Al-1.66
2H2O(l) + 2e- = H2(g) + 2OH - -0.83
Cr3+ + 3e- =Cr-0.74
Fe2+ + 2e- =Fe-0.41
2H+ + e- =H20.00
Sn4+ + 2e- =Sn2++0.15
Cu2+ + e- =Cu++0.16
Ag+ + e- =Ag+0.80
Br2 + 2e- =2Br-+1.07
Cl2 + 2e- =2Cl-+1.36
MnO4-2 + 8H+ + 5e- =Mn+2 + 4H2O+1.49

In order come tell i beg your pardon is the strongest reducing agent, readjust the sign of its corresponding reduction potential in bespeak to make it oxidation potential. The larger the number the stronger a reducing certified dealer it is.

For instance if one to be to list Cu, Cl-, Na and also Cr in order, one would acquire their palliation potential, readjust the sign to do it oxidation potential and also list lock from biggest to least. One will acquire Na, Cr, Cu and also Cl-; Na gift the the strongest reducing agent and also Cl- gift the weakest one.

A couple of good typical reducing agents include energetic metals such as potassium, calcium, barium, sodium and magnesium and also, compounds that contain the H- ion, those being NaH, LiAlH4 and CaH2.

Also, some elements and compounds have the right to be both reduce or oxidizing agents. Hydrogen gas is a reducing agent as soon as it reacts through non-metals and an oxidizing agent when it reacts through metals.

2Li(s) + H2(g) -->2LiH(s) hydrogen acts together an oxidizing agent because it accepts an electron donation from lithium, which causes Li to be oxidized.

Half reaction 2Li(s)0 -->2Li(s)+1 + 2e-::::: H20(g) + 2e- --> 2H-1(g)

H2(g) + F2(g) --> 2HF(g) hydrogen acts together a reducing agent since it donates its electrons to fluorine, which permits fluorine to it is in reduced.

Half reactions H20(g) --> 2H+1(g) + 2e-:::::F20(g) + 2e- --> 2F-1(g)

importance of reducing and oxidizing agents

Reducing agents and oxidizing agents space the ones responsible for corrosion, i m sorry is the “degradation of steels as a result of electrochemical activity”3. Corrosion calls for an anode and also cathode to take it place. The anode is an aspect that loses electrons (reducing agent), hence oxidation always occurs in the anode, and the cathode is an element that gains electrons (oxidizing agent), therefore reduction always occurs in the cathode. Corrosion occurs whenever there’s a difference in oxidation potential. As soon as this is present, the anode steel will start deteriorating offered that there is an electrical connection and the presence of an electrolyte.

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example of oxidation reaction

The formation of iron(III) oxide;

4Fe + 3O2 → 2Fe2O3

In the above equation, the steel (Fe) has actually an oxidation variety of 0 before and also 3+ after the reaction. Because that oxygen (O) the oxidation number began as 0 and decreased come 2−. These alters can be viewed as two "half-reactions" that happen concurrently:

Oxidation fifty percent Reaction: Fe0 → Fe3+ + 3e− Reduction fifty percent Reaction: O2 + 4e− → 2 O2−

Iron III (Fe) has been oxidized because the oxidation number increased and is the reducing agent because it provided electrons come the oxygen (O).Oxygen (O) has actually been reduced due to the fact that the oxidation number has decreased and also is the oxidizing agent due to the fact that it took electrons from iron (Fe)

usual reducing agents

Ferrous ionNascent hydrogenSulfite compounds

common reducing agents and also their products

H2 HydrogenH+, H2O
metalsmetal ions
CCO2 carbon dioxide
hydrocarbonsCO2 carbon dioxide, H2O

see also


2,3http://www.siliconfareast.com/ox_potential.htmhttp://www.chemed.chem.purdue.edu/genchem/topicreview/bp/ch19/oxred_3.htmlhttp://www.members.aol.com/logan20/agents.html"Chemical Principles: The search for Insight", 3rd Edition. Peter Atkins and also Loretta Jones pg. F76
This short article is licensed under the GNU totally free Documentation License. It uses material from the Wikipedia short article "Reducing_agent". A perform of authors is available in Wikipedia.