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3Cu2O + 2KMnO4 + H2O → 6CuO + 2MnO2 + 2KOH

3Cu₂O + 2KMnO₄ + H₂O → 6CuO + 2MnO₂ + 2KOH

Last updated: June 13, 2022

Reaction of copper(I) oxide and potassium permanganate under neutral condition: 3Cu₂OCopper(I) oxide + 2KMnO₄Potassium permanganate + H₂OWater
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6CuOCopper(II) oxide + 2MnO₂Manganese(IV) oxide + 2KOHPotassium hydroxide

The reaction of copper(I) oxide, potassium permanganate, and water yields copper(II) oxide, manganese(IV) oxide, and potassium hydroxide (Other reactions are here). This reaction is an oxidation-reduction reaction and is classified as follows:

Reaction of oxidizable species and oxidizing species under neutral condition

Table of contents

Reaction data

Chemical equation

Reaction of copper(I) oxide and potassium permanganate under neutral condition: 3Cu₂OCopper(I) oxide + 2KMnO₄Potassium permanganate + H₂OWater
⟶
6CuOCopper(II) oxide + 2MnO₂Manganese(IV) oxide + 2KOHPotassium hydroxide

General equation

Reaction of oxidizable species and oxidizing species under neutral condition: Oxidizable speciesReducing agent + Oxidizing speciesOxidizing agent + H₂ONon-redox agent
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ProductOxidation product + ProductReduction product

Oxidation state of each atom

Reaction of copper(I) oxide and potassium permanganate under neutral condition

Reactants

Chemical formula	Name	Coefficient	Type	Type in general equation
Cu₂O	Copper(I) oxide	3	Reducing	Oxidizable
KMnO₄	Potassium permanganate	2	Oxidizing	Oxidizing
H₂O	Water	1	–	Water

Products

Chemical formula	Name	Coefficient	Type	Type in general equation
CuO	Copper(II) oxide	6	Oxidized	–
MnO₂	Manganese(IV) oxide	2	Reduced	–
KOH	Potassium hydroxide	2	–	–

Thermodynamic changes

Changes in standard condition (1)

Reaction of copper(I) oxide and potassium permanganate under neutral condition ◆ Δ_rG −316.3 kJ/mol K 2.59 × 10⁵⁵ pK −55.41: 3Cu₂OCrystalline solid + 2KMnO₄Crystalline solid + H₂OLiquid
⟶
6CuOCrystalline solid + 2MnO₂Crystalline solid + 2KOHCrystalline solid

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	−367.4	−316.3	−173.1	−9.5
per 1 mol of Copper(I) oxide	−122.5	−105.4	−57.70	−3.2
per 1 mol of Potassium permanganate	−183.7	−158.2	−86.55	−4.8
per 1 mol of Water	−367.4	−316.3	−173.1	−9.5
per 1 mol of Copper(II) oxide	−61.23	−52.72	−28.85	−1.6
per 1 mol of Manganese(IV) oxide	−183.7	−158.2	−86.55	−4.8
per 1 mol of Potassium hydroxide	−183.7	−158.2	−86.55	−4.8

Changes in standard condition (2)

Reaction of copper(I) oxide and potassium permanganate under neutral condition: 3Cu₂OCrystalline solid + 2KMnO₄Crystalline solid + H₂OLiquid
⟶
6CuOCrystalline solid + 2MnO₂Amorphous solidprecipitated + 2KOHCrystalline solid

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	−332.3	–	–	–
per 1 mol of Copper(I) oxide	−110.8	–	–	–
per 1 mol of Potassium permanganate	−166.2	–	–	–
per 1 mol of Water	−332.3	–	–	–
per 1 mol of Copper(II) oxide	−55.38	–	–	–
per 1 mol of Manganese(IV) oxide	−166.2	–	–	–
per 1 mol of Potassium hydroxide	−166.2	–	–	–

Changes in aqueous solution

Reaction of copper(I) oxide and potassium permanganate under neutral condition ◆ Δ_rG −453.4 kJ/mol K 2.71 × 10⁷⁹ pK −79.43: 3Cu₂OCrystalline solid + 2KMnO₄Ionized aqueous solution + H₂OLiquid
⟶
6CuOCrystalline solid + 2MnO₂Crystalline solid + 2KOHIonized aqueous solution

	Standard enthalpy of reaction Δ_rH° kJ · mol⁻¹	Standard Gibbs energy of reaction Δ_rG° kJ · mol⁻¹	Standard entropy of reaction Δ_rS° J · K⁻¹ · mol⁻¹	Standard heat capacity of reaction at constant pressure Δ_rC_p° J · K⁻¹ · mol⁻¹
per 1 mol of Equation	−569.4	−453.4	−391.7	−37.3
per 1 mol of Copper(I) oxide	−189.8	−151.1	−130.6	−12.4
per 1 mol of Potassium permanganate	−284.7	−226.7	−195.8	−18.6
per 1 mol of Water	−569.4	−453.4	−391.7	−37.3
per 1 mol of Copper(II) oxide	−94.90	−75.57	−65.28	−6.22
per 1 mol of Manganese(IV) oxide	−284.7	−226.7	−195.8	−18.6
per 1 mol of Potassium hydroxide	−284.7	−226.7	−195.8	−18.6

Thermodynamic data of reactants

Chemical formula	Standard enthalpy of formation Δ_fH° kJ · mol⁻¹	Standard Gibbs energy of formation Δ_fG° kJ · mol⁻¹	Standard molar entropy S° J · K⁻¹ · mol⁻¹	Standard molar heat capacity at constant pressure C_p° J · K⁻¹ · mol⁻¹
Cu₂O (cr)	-168.6^[1]	-146.0^[1]	93.14^[1]	63.64^[1]
KMnO₄ (cr)	-837.2^[1]	-737.6^[1]	171.71^[1]	117.57^[1]
KMnO₄ (ai)	-793.8^[1]	-730.5^[1]	293.7^[1]	-60.2^[1]
H₂O (cr)	–	–	–	–
H₂O (l)	-285.830^[1]	-237.129^[1]	69.91^[1]	75.291^[1]
H₂O (g)	-241.818^[1]	-228.572^[1]	188.825^[1]	33.577^[1]

* (cr):Crystalline solid, (ai):Ionized aqueous solution, (l):Liquid, (g):Gas

Thermodynamic data of products

Chemical formula	Standard enthalpy of formation Δ_fH° kJ · mol⁻¹	Standard Gibbs energy of formation Δ_fG° kJ · mol⁻¹	Standard molar entropy S° J · K⁻¹ · mol⁻¹	Standard molar heat capacity at constant pressure C_p° J · K⁻¹ · mol⁻¹
CuO (cr)	-157.3^[1]	-129.7^[1]	42.63^[1]	42.30^[1]
MnO₂ (cr)	-520.03^[1]	-465.14^[1]	53.05^[1]	54.14^[1]
MnO₂ (am) precipitated	-502.5^[1]	–	–	–
KOH (cr)	-424.764^[1]	-379.08^[1]	78.9^[1]	64.9^[1]
KOH (g)	-231.0^[1]	-232.6^[1]	238.3^[1]	49.20^[1]
KOH (ai)	-482.37^[1]	-440.50^[1]	91.6^[1]	-126.8^[1]
KOH (cr) 1 hydrate	-748.9^[1]	-645.1^[1]	117.2^[1]	–
KOH (cr) 2 hydrate	-1051.0^[1]	-887.3^[1]	150.6^[1]	–

* (cr):Crystalline solid, (am):Amorphous solid, (g):Gas, (ai):Ionized aqueous solution

References

List of references

1
Janiel J. Reed (1989)
The NBS Tables of Chemical Thermodynamic Properties: Selected Values for Inorganic and C1 and C2 Organic Substances in SI Units
https://doi.org/10.18434/M32124
National Institute of Standards and Technology (NIST)
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