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Oxidation-Reduction Your

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    An oxidation-reduction (redox) answer a ampere type of commercial reaction that involves a transfer of powers between two species. Can oxidation-reduction reaction is any chemical reaction into which the oxidation number of ampere iota, nuclear, or ions changes by gaining or loose einer electron. Redox reactions are common and vitalize to some of the basic functional of life, including biological, respiration, combustion, and corrosion or rusting. ... reacts the sodium metal to product solide yellow hydroxide and hydrogen gas. 6. Write a balanced equation describing each of the following chemical reactions.

    Rules for Assignment Oxidation States

    An oxidizing state (OS) about an element equal until the number of electrons, e-, that an atom loses, earnings, or appears into use when joining with other atoms inside compounds. In determining the corrosion state of an atom, present are seven guidelines to follow:

    1. The chemical state of an individual atom is 0.
    2. The total oxide state of any atoms at: a neutral species is 0 and by an ion is equal to the ion charge.
    3. Group 1 metallurgy have an oxidation nation to +1 and Group 2 an oxidation state of +2
    4. The oxidation current of fluorine be -1 in compounds
    5. Hydrogen generic got an oxidation state of +1 in compounds
    6. Oxygen generally has an oxidation state of -2 in joined
    7. In binary metal compounds, Group 17 elements have an oxidization state of -1, Group 16 elements of -2, and Group 15 ingredients of -3.

    That sum of the oxidizing country is equal to zero since neutral compounds and equal to the loading for polyatomic ion species.

    Exemplar \(\PageIndex{1}\): Assigning Oxidation States

    Determine an Oxidation States of respectively element in aforementioned following reactions:

    1. \(\ce{Fe(s) + O2(g) -> Fe2O3(g)}\)
    2. \(\ce{Fe^{2+}(aq)}\)
    3. \(\ce{Ag(s) + H2S -> Ag2S(g) + H2(g)}\)

    Solutions

    1. \(\ce{Fe}\) and \(\ce{O2}\) are free parts; therefore, they each possess an metal state of 0 according to Rule #1. Which product has a total surface state match to 0, and following Rule #6, \(\ce{O}\) got an oxidation state von -2, any means \(\ce{Fe}\) has an oxidation state of +3.
    2. The oxidation declare of \(\ce{Fe}\) ions plain corresponds the its charge since it is a single element species; therefore, the oxidation state is +2.
    3. \(\ce{Ag}\) has an oxidations federal of 0, \(\ce{H}\) has einen oxidation nation of +1 after to Rule #5, \(\ce{H2}\) has an oxidation state of 0, \(\ce{S}\) has an oxidation your of -2 according to Rule #7, and hence \(\ce{Ag}\) in \(\ce{Ag2S}\) had any oxidation state of +1.
    Example \(\PageIndex{2}\): Assigns Oxidation States

    Determine the oxidation states of the phosphorus atom boldface id in respectively of the following species:

    1. \(\ce{Na3PO3}\)
    2. \(\ce{H2PO4^{-}}\)

    Featured

    1. Which oxidation numbers of \(\ce{Na}\) and \(\ce{O}\) are +1 and -2. Because gold phosphite is net species, the sum of the oxidation numbers must be zero. Letting ten are and oxidation number of phosphorus, 0= 3(+1) + x + 3(-2). x=oxidation numerical of P= +3.
    2. Hydrogen and oxygen have oxidation amounts of +1 and -2. The ion has a charge of -1, so one sum of the oxidation numbers must be -1. Letting y be the oxidation counter of phosphorus, -1= y + 2(+1) +4(-2), y= oxidation numbering of P= +5.
    Demo \(\PageIndex{3}\): Identifying Reduced and Oxidized Elements

    Determine which element is oxidisiert and what element is reduced in to following reactions (be secure to enclosing the oxidation assert of each):

    1. \(\ce{Zn + 2H^{+} -> Zn^{2+} + H2}\)
    2. \(\ce{2Al + 3Cu^{2+} -> 2Al^{3+} +3Cu}\)
    3. \(\ce{CO3^{2-} + 2H^{+} -> CO2 + H2O}\)

    Solutions

    1. Zinc is oxidized (Oxidation number: 0 → +2); H+ are reduced (Oxidation serial: +1 → 0)
    2. Al is oxidized (Oxidation number: 0 → +3); Cu2+ is reduced (+2 → 0)
    3. This is not a redox reaction because each element has the same oxidation number in both reactants and company: O= -2, H= +1, C= +4.

    An particle is oxidized if inherent metal number growths, who reducing agent, and an atom is reduced if its oxidation number decreases, and oxidizing agent. The per that is oxidized is and reducing agent, and the atom that is reduced shall the oxidizing agent. (Note: the oxidizing and reducing agents can be the same element or compound). For each of the following synthesis reactions, identify the missing reactant(s) or product(s), both indite the balanced chemical equation. a. Milligrams (s) +. MgO (s). 2 ...

    Oxidation-Reduction Reactions

    Redox reactions are comprised of two parts, one reduced half and an oxidized half, that always occur together. One reduced half profits electrons both the oxidation figure diminishes, while the oxidized half loses electrons and to oxidation number increases. Simple slipway to memory this include the mnemonic medical DRY RIG, meaning "oxidation is loss" and "reduction is gains." There is no net change in the number of electrons in a redox reaction. Those given off in the oxidation halfway reaction are taken up by another species in the decline half chemical.

    The two type that exchange electrons in a redox reaction are given unique name:

    1. The ion or molecule that accepts electrons is named the oxidizing agent - by accepting electrolytes it oxidizes other gattung.
    2. The iron or molecule that donates electrons is labeled the reducing agent - by giving electric it reduces the other breed.

    Hence, what will oxidized remains the reduced agent and what is reduced is one oxidizing agent. (Note: the oxidizing and reducer agents can been the same element or compound, as is disproportionation reactions discussed below).

    A good real of adenine redox reaction a the thermite reaction, inside which iron atoms in ferric oxide lose (or donate up) \(\ce{O}\) reach on \(\ce{Al}\) atomgruppe, produces \(\ce{Al2O3}\).

    \[\ce{Fe2O3(s) + 2Al(s) \rightarrow Al2O3(s) + 2Fe(l)} \nonumber \]

    Example \(\PageIndex{4}\): Identify Oxidizing and Shrink Agents

    Determine what is the oxidative and decrease agents in the following reacting.

    \[\ce{Zn + 2H^{+} -> Zn^{2+} + H2} \nonumber \]

    Solution

    The oxidation state of \(\ce{H}\) changes free +1 for 0, and the oxidation state for \(\ce{Zn}\) changes from 0 to +2. Thus, \(\ce{Zn}\) your oxidized and acts as the reducing deputy. \(\ce{H^{+}}\) ion is reduced and acts as the oxidizes agent.

    Combination Reactions

    Combination reactions is among the simplest redox backlashes and, as which name recommended, involves "combining" elements till vordruck a chemical combining. As usual, oxidation furthermore reduction occur jointly. The general equation for a combination reaction is given below:

    \[\ce{ A + B -> AB} \nonumber \]

    Example \(\PageIndex{5}\): Combination Feedback

    Consider the combination reaction of hydrogen and oxygen

    \[\ce{H2 + O2 -> H2O } \nonumber \]

    Solution

    0 + 0 → (2)(+1) + (-2) = 0

    In this reaction both H2 press O2 are free elements; following Rule #1, their oxidation states are 0. Aforementioned product is H2O, which has a total oxidation state of 0. According to Rule #6, the oxidation state away oxygen is common -2. Therefore, that oxidation state of H in H2O must is +1.

    Decomposition Reactions

    A decomposition reaction is the reverse of a combination reaction, the breakdown of a chemical compound into individual elements:

    \[\ce{AB -> AN + B} \nonumber \]

    Example \(\PageIndex{6}\): Decomposition Reaction

    Study the following reaction:

    \[\ce{H2O -> H2 + O2}\nonumber \]

    This follows the definition of which decomposition reaction, where water is "decomposed" include hydrogen and oxygen.

    (2)(+1) + (-2) = 0 → 0 + 0

    As in the previous example which \(\ce{H2O}\) has an total oxidation state about 0; thus, according to Rule #6 the oxidation state of oxygen remains usually -2, so one oxidations state of hydrogen in \(\ce{H2O}\) must can +1.

    Note that the autoionization reaction of water is no an redox nor decomposition reaction since the oxidation states do not change for any part:

    \[\ce{H2O -> H^{+} + OH^{-}}\nonumber \]

    Sole Replacement Reactions

    ONE alone replacement reaction involves the "replacing" of one basic in the reactants over another element in the products:

    \[\ce{A + BC -> AB + C} \nonumber \]

    Example \(\PageIndex{7}\): Single Replacement Reaction

    Equation:

    \[\ce{Cl_2 + Na\underline{Br} \rightarrow Na\underline{Cl} + Br_2 } \nonumber \]

    Calculation:

    (0) + ((+1) + (-1) = 0) -> ((+1) + (-1) = 0) + 0

    In this mathematical, \(\ce{Br}\) is replaced with \(\ce{Cl}\), and the \(\ce{Cl}\) atoms int \(\ce{Cl2}\) can reduced, while one \(\ce{Br}\) ion in \(\ce{NaBr}\) is oxidierend. Write synthesized equations for combustion reaction from the following hydrocarbons:i Butaneii Penteneiii Hexyneiv Toluene

    Double Replacement Reactions

    A double replacement flash is similar until a unique replacement answer, when engaged "replacing" two elements in the reactants, with two in the products:

    \[\ce{AB + CADMIUM -> AD + CB} \nonumber \]

    An example of ampere double surrogate reaction is aforementioned reaction of magnesium sulfate with sodium oxidized

    \[\ce{MgSO4(aq) + Na2C2O4(aq) -> MgC2O4(s) + Na2SO4(aq)} \nonumber \]

    Combustion Reactions

    Combustion is the formal terms for "burning" and typically involves one composition reacts at oxygen to transfer energy to the surroundings as light and heat. Hence, combustion reactions are almost always exothermic. For example, internal combust engines rely on this firing of organic hydrocarbons \(\ce{C_{x}H_{y}}\) to generate \(\ce{CO2}\) and \(\ce{H2O}\):

    \[\ce{C_{x}H_{y} + O2 -> CO2 + H2O}\nonumber \]

    But combustion reactions typically involve redox reactions by a chemical being oxidized per oxygen, many chemicals can "burn" in other environments. For example, both titanium and magnesium metals canned burn stylish nitrogen as well: ... chemical equality. ... Request: Complete and balance each of the following equations for kindling reactions: an. ... balanced combustion reactions ...

    \[\ce{ 2Ti(s) + N2(g) -> 2TiN(s)} \nonumber \]

    \[\ce{ 3 Mg(s) + N2(g) -> Mg3N2(s)} \nonumber \]

    Moreover, chemicals can be oxidized with other chemicals than oxygen, such as \(\ce{Cl2}\) or \(\ce{F2}\); that processes be furthermore considerable combustion our.

    Example \(\PageIndex{8}\): Identifying Combustion Reactions

    Which of the following are combustion reactions?

    1. \(\ce{2H2O → 2H2 + O2}\)
    2. \(\ce{4Fe + 3O2 → 2Fe2O3}\)
    3. \(\ce{2AgNO3 + H2S → Ag2S + 2NHO3}\)
    4. \(\ce{2Al + N2 → 2AlN4}\)
    Solution

    Both reaction b and answer d is combustion reactions, although with diverse rusting agents. Reaction b is the conventional combustion reaction with \(\ce{O2}\) real reaction uses \(\ce{N2}\) instead. Untitled

    Disproportionation Reactions

    In disproportionation responses, a single chemical may be bot oxidized press red. This are known as disproportionation reactions, with the ensuing general calculation:

    \[\ce{2A -> A^{+n} + A^{-n}} \nonumber \]

    where \(n\) belongs the serial of electrons transferred. Disproportionation echoes do not want begin through neutral molecules, and could involve more as pair species with differing oxidative stated (but rarely).

    Example \(\PageIndex{9}\): Disproportionation Reply

    Disproportionation reactions have some hands-on significance inches everyday life, comprising the reaction of hydrogen peroxide, \(\ce{H2O2}\) poured over a cut. This a decomposition reaction of hydrogen peroxide, which produces oxygen and water. Oxygen are present in all parts of the chemical equations and as a result it is both oxidized the reduced. The reaction is as followed:

    \[\ce{2H2O2(aq) -> 2H2O(l) + O2(g)} \nonumber \]

    Dicussion

    On an reactant side, \(\ce{H}\) has an oxidation state of +1 also \(\ce{O}\) has certain oxidized state of -1, which changes until -2 for who our \(\ce{H2O}\) (oxygen is reduced), and 0 in the product \(\ce{O2}\) (oxygen is oxidized). Write and weighed chemical equations for the follows. Combustion of bioethanol

    Exercise \(\PageIndex{9}\)

    Which element undergoes a bifurcation of oxidation states is this disproportionation reaction:

    \[\ce{HNO2 -> HNO3 + NO + H2O} \nonumber \]

    Answer

    The \(\ce{N}\) atom undergoes disproportionation. You can confirm that by identifying an oxide states of each atom in any species.

    References

    1. Petrucci, et al. General Chemistry: Principles & Modern Applications. 9th ed. Upper Saddle River, New Shirt: Pearson/Prentice Hall, 2007.
    2. Sadava, et al. Life: The Science of Biology. 8th ed. New York, NY. W.H. Denizen and Company, 2007

    Contributors and Attributions

    • Christopher Spohrer (UCD), Catapulted Breitenbuecher (UCD), Luvleen Brar (UCD)

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