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Potassium acetate

Potassium acetate

Last updated: March 19, 2023

Potassium acetate is an organic compound with formula CH₃COOK.

Table of contents

Names

List of substance names

Nomenclature

Name

Typical name: Potassium acetate

Compositional nomenclature: Potassium acetate
★Preferred IUPAC name; Potassium ethanoate

IUPAC acceptable common names: Potassium acetate

Formulae and structures

List of formulae

Formula name

Formula

Typical formula: CH₃COOK

Compositional formula: CH₃COOK

Structural formula

Structural formula with no conjugation

Structural formula with no C–H bond

Structural formula with no conjugation and no C–H bond

Skeletal formula

Skeletal formula with no conjugation

Lewis structure

Colored Lewis structure

Properties

List of substance properties

Item

Value

Name: Potassium acetate

Formula: CH₃COOK

Appearance: Colorless solid

Odor: Odorless

Molar mass: 98.142 g/mol

Density: 1.57 g/cm³^[1][2]
Solid

Melting point: 292 °C^[1]; 309 °C^[2]

Boiling point: Decompose^[1]
→ K₂CO₃, CH₃COCH₃

Constituents

Constituent ions

Ion	Name	Charge number	Number
K⁺	Potassium ion	1	1
CH₃COO⁻	Acetate ion	-1	1

Constituent atoms

Atom	Name	Oxidation state	Number
C	Carbon	−3	1
H	Hydrogen	+1	3
C	Carbon	+3	1
O	Oxygen	−2	2
K	Potassium	+1	1

Ratio of atoms

Atom	Atomic weight	Number	Atomic ratio	Weight ratio
C	12.011	2	25.00%	24.48%
H	1.008	3	37.50%	3.08%
O	15.999	2	25.00%	32.60%
K	39.0983	1	12.50%	39.84%

Thermodynamic properties

Phase transition properties

Item

Value

Enthalpy of fusion: 7.65 kJ · mol⁻¹^[1]
at 309°C

Enthalpy of vaporization: –

Enthalpy of vaporization at 25°C: –

Enthalpy of other transition: –

Standard thermodynamic properties

State	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
Crystalline solid	−723.0^[3]	–	–	–
Ionized aqueous solution	−738.39^[3]	−652.58^[3]	189.1^[3]	15.5^[3]

Solubility

Qualitative solubility

Reactive

Miscible

Very soluble: H₂OWater
C₂H₅OHEthanol

Soluble

Slightly soluble

Very slightly soluble

Insoluble

Solubility in water (g/100 g)^[1]

0°C	10°C	20°C	30°C	40°C	60°C	80°C	90°C
216	233	256	283	324	350	381	398

Solubility in water (g/100 g)^[4]

0.1°C	5°C	10°C	15°C	20°C	25°C	30°C	35°C	38°C	40°C	41°C	42°C	45°C	50°C	60°C	70°C	80°C	90°C	96°C
216.7	223.9	233.9	243.1	255.6	269.4	283.8	301.8	314.2	323.3	327.7	329	332.2	337.3	350	364.8	380.1	396.3	406.5

Solubility in water (g/100 g)^[4]

25°C
219.6

Solubility in ethanol (g/100 g, 20%)^[4]

25°C
219.6

Solubility in ethanol (g/100 g, 40%)^[4]

25°C
192.4

Solubility in ethanol (g/100 g, 50%)^[4]

25°C
171.8

Solubility in ethanol (g/100 g, 60%)^[4]

25°C
147.5

Solubility in ethanol (g/100 g, 70%)^[4]

25°C
118.3

Solubility in ethanol (g/100 g, 80%)^[4]

25°C
87.6

Solubility in ethanol (g/100 g, 90%)^[4]

25°C
52.9

Solubility in ethanol (g/100 g, 95%)^[4]

25°C
34.2

Solubility in ethanol (g/100 g)^[4]

25°C
16.3

Solubility curve (g/100 g)

Preparations

Chemical reactions

Electrolytic dissociation

Electrolytic dissociation of potassium acetate yields potassium ion and acetate ion.

Electrolytic dissociation of potassium acetate: CH₃COOKPotassium acetate
⟶
K⁺Potassium ion + CH₃COO⁻Acetate ion

Reaction with strong acid

The reaction of potassium acetate and strong acid yields salt of strong acid and acetic acid.

Reaction of potassium acetate and hydrogen chloride ◆ Δ_rG −27.14 kJ/mol K 5.68 × 10⁴ pK −4.75: CH₃COOKPotassium acetate + HClHydrogen chloride
⟶
KClPotassium chloride + CH₃COOHAcetic acid

Reaction of potassium acetate and hydrogen bromide ◆ Δ_rG −27.15 kJ/mol K 5.71 × 10⁴ pK −4.76: CH₃COOKPotassium acetate + HBrHydrogen bromide
⟶
KBrPotassium bromide + CH₃COOHAcetic acid

Reaction of potassium acetate and hydrogen iodide ◆ Δ_rG −27.16 kJ/mol K 5.73 × 10⁴ pK −4.76: CH₃COOKPotassium acetate + HIHydrogen iodide
⟶
KIPotassium iodide + CH₃COOHAcetic acid

Reaction of potassium acetate and sulfuric acid ◆ Δ_rG −54.30 kJ/mol K 3.26 × 10⁹ pK −9.51: 2CH₃COOKPotassium acetate + H₂SO₄Sulfuric acid
⟶
K₂SO₄Potassium sulfate + 2CH₃COOHAcetic acid

Reaction of potassium acetate and nitric acid ◆ Δ_rG −27.16 kJ/mol K 5.73 × 10⁴ pK −4.76: CH₃COOKPotassium acetate + HNO₃Nitric acid
⟶
KNO₃Potassium nitrate + CH₃COOHAcetic acid

Reaction with nonvolatile acid

The reaction of potassium acetate and nonvolatile acid yields salt of non volatile acid and acetic acid.

Reaction of potassium acetate and phosphoric acid ◆ Δ_rG 42.2 kJ/mol K 0.40 × 10⁻⁷ pK 7.39: 3CH₃COOKPotassium acetate + H₃PO₄Phosphoric acid
⟶
K₃PO₄Potassium phosphate + 3CH₃COOHAcetic acid

Reaction of potassium acetate and sulfuric acid ◆ Δ_rG −38.53 kJ/mol K 5.63 × 10⁶ pK −6.75: CH₃COOKPotassium acetate + H₂SO₄Sulfuric acid
⟶
KHSO₄Potassium hydrogensulfate + CH₃COOHAcetic acid

Reaction of potassium acetate and perchloric acid ◆ Δ_rG −27.15 kJ/mol K 5.71 × 10⁴ pK −4.76: CH₃COOKPotassium acetate + HClO₄Perchloric acid
⟶
KClO₄Potassium perchlorate + CH₃COOHAcetic acid

Reaction of potassium acetate and bromic acid ◆ Δ_rG −27.15 kJ/mol K 5.71 × 10⁴ pK −4.76: CH₃COOKPotassium acetate + HBrO₃Bromic acid
⟶
KBrO₃Potassium bromate + CH₃COOHAcetic acid

Reaction of potassium acetate and iodic acid ◆ Δ_rG −22.5 kJ/mol K 8.75 × 10³ pK −3.94: CH₃COOKPotassium acetate + HIO₃Iodic acid
⟶
KIO₃Potassium iodate + CH₃COOHAcetic acid

Reaction with oxidizing species

The reaction of potassium acetate and oxidizing species yields a variety of products.

Reaction of potassium acetate and oxygen ◆ Δ_rG −1724.0 kJ/mol K 1.08 × 10³⁰² pK −302.03: 2CH₃COOKPotassium acetate + 4O₂Oxygen
⟶
K₂CO₃Potassium carbonate + 3H₂CO₃Carbonic acid

Reaction of potassium acetate and oxygen ◆ Δ_rG −800.6 kJ/mol K 1.82 × 10¹⁴⁰ pK −140.26: 4CH₃COOKPotassium acetate + 2O₂Oxygen
⟶
2K₂CO₃Potassium carbonate + 3CH₃COOHAcetic acid

Reaction of potassium acetate and chlorine ◆ Δ_rG −456.05 kJ/mol K 7.88 × 10⁷⁹ pK −79.90: CH₃COOKPotassium acetate + 2Cl₂Chlorine
⟶
KClPotassium chloride + 3HClHydrogen chloride + CO₂Carbon dioxide + CCarbon

Reaction of potassium acetate and potassium permanganate ◆ Δ_rG −5697.7 kJ/mol K 1.56 × 10⁹⁹⁸ pK −998.19: 14CH₃COOKPotassium acetate + 16KMnO₄Potassium permanganate
⟶
16MnManganese + 15K₂CO₃Potassium carbonate + 13CO₂↑Carbon dioxide + 21H₂OWater

Reaction with reducible species

The reaction of potassium acetate and reducible species yields a variety of products.

Reaction of potassium acetate and iodine ◆ Δ_rG −104.33 kJ/mol K 1.90 × 10¹⁸ pK −18.28: CH₃COOKPotassium acetate + 2I₂Iodine
⟶
KIPotassium iodide + 3HI↑Hydrogen iodide + CO₂↑Carbon dioxide + CCarbon

Reaction of potassium acetate and manganese(IV) oxide ◆ Δ_rG −1044.1 kJ/mol K 8.29 × 10¹⁸² pK −182.92: 2CH₃COOKPotassium acetate + 8MnO₂Manganese(IV) oxide
⟶
3MnCO₃Manganese(II) carbonate + 5MnOManganese(II) oxide + K₂CO₃Potassium carbonate + 3H₂OWater

Reaction of potassium acetate and iron(III) oxide ◆ Δ_rG −114.6 kJ/mol K 1.19 × 10²⁰ pK −20.08: 2CH₃COOKPotassium acetate + 21Fe₂O₃Iron(III) oxide
🔥
⟶
3FeCO₃Iron(II) carbonate + 13Fe₃O₄Iron(II,III) oxide + K₂CO₃Potassium carbonate + 3H₂OWater

Reaction of potassium acetate and manganese(IV) oxide ◆ Δ_rG −590.3 kJ/mol K 2.61 × 10¹⁰³ pK −103.42: 2CH₃COOKPotassium acetate + 4MnO₂Manganese(IV) oxide
⟶
MnCO₃Manganese(II) carbonate + 3Mn(OH)₂Manganese(II) hydroxide + K₂CO₃Potassium carbonate + 2CCarbon

Reaction with reducing species

The reaction of reducing species and potassium acetate yields a variety of products.

Reaction of hydrogen and potassium acetate ◆ Δ_rG −72.0 kJ/mol K 4.11 × 10¹² pK −12.61: 8H₂Hydrogen + 2CH₃COOKPotassium acetate
🔥
⟶
K₂OPotassium oxide + 3H₂OWater + 4CH₄Methane

Reaction of hydrogen sulfide and potassium acetate ◆ Δ_rG −79.52 kJ/mol K 8.54 × 10¹³ pK −13.93: H₂SHydrogen sulfide + 2CH₃COOKPotassium acetate
⟶
K₂SO₄Potassium sulfate + 2CH₄Methane + 2CCarbon

Reaction of hydrogen and potassium acetate ◆ Δ_rG −196.9 kJ/mol K 3.13 × 10³⁴ pK −34.50: 4H₂Hydrogen + CH₃COOKPotassium acetate
⟶
KOHPotassium hydroxide + H₂OWater + 2CH₄Methane

Reaction of hydrogen sulfide and potassium acetate ◆ Δ_rG −76.5 kJ/mol K 2.52 × 10¹³ pK −13.40: 9H₂SHydrogen sulfide + 2CH₃COOKPotassium acetate
🔥
⟶
8SSulfur + 4H₂OWater + K₂SPotassium sulfide + 4CH₄Methane

Reaction with oxidizable species under acidic condition

The reaction of oxidizable species, potassium acetate, and hydrogen ion yields a variety of products.

Reaction of copper and potassium acetate under acidic condition ◆ Δ_rG −24.69 kJ/mol K 2.12 × 10⁴ pK −4.33: 2CuCopper + CH₃COOKPotassium acetate + 5H⁺Hydrogen ion
🔥
⟶
2Cu²⁺Copper(II) ion + 2H₂OWater + K⁺Potassium ion + CH₄↑Methane + CCarbon

Reaction of copper and potassium acetate under acidic condition ◆ Δ_rG 55.57 kJ/mol K 0.18 × 10⁻⁹ pK 9.74: 4CuCopper + CH₃COOKPotassium acetate + 9H⁺Hydrogen ion
🔥
⟶
4Cu²⁺Copper(II) ion + 2H₂OWater + K⁺Potassium ion + 2CH₄↑Methane

Reaction of potassium iodide and potassium acetate under acidic condition ◆ Δ_rG 271.85 kJ/mol K 0.24 × 10⁻⁴⁷ pK 47.63: 8KIPotassium iodide + CH₃COOKPotassium acetate + 9H⁺Hydrogen ion
🔥
⟶
9K⁺Potassium ion + 4I₂Iodine + 2H₂OWater + 2CH₄↑Methane

Reaction of potassium iodide and potassium acetate under acidic condition ◆ Δ_rG 1005.96 kJ/mol K 0.58 × 10⁻¹⁷⁶ pK 176.24: 32KIPotassium iodide + 7CH₃COOKPotassium acetate + 39H⁺Hydrogen ion
🔥
⟶
39K⁺Potassium ion + 16I₂Iodine + 3CH₃COOHAcetic acid + 8H₂OWater + 8CH₄↑Methane

Precipitation reaction

When a certain chemical species is present in aqueous solution, it reacts with potassium acetate to form a precipitate.

Reaction of potassium acetate and ammonium chromate ◆ Δ_rG 0.00 kJ/mol K 1.00 × 10⁰ pK 0.00: 2CH₃COOKPotassium acetate + (NH₄)₂CrO₄Ammonium chromate
💧
⟶
K₂CrO₄↓Potassium chromate + 2CH₃COONH₄Ammonium acetate

Reaction of potassium acetate and sodium chromate ◆ Δ_rG 0.04 kJ/mol K 0.98 × 10⁰ pK 0.01: 2CH₃COOKPotassium acetate + Na₂CrO₄Sodium chromate
💧
⟶
K₂CrO₄↓Potassium chromate + 2CH₃COONaSodium acetate

Reaction of potassium acetate and calcium chromate: 2CH₃COOKPotassium acetate + CaCrO₄Calcium chromate
💧
⟶
K₂CrO₄↓Potassium chromate + Ca(CH₃COO)₂Calcium acetate

Reaction of magnesium hydrogencarbonate and potassium acetate: Mg(HCO₃)₂Magnesium hydrogencarbonate + 2CH₃COOKPotassium acetate
💧
⟶
MgCO₃↓Magnesium carbonate + 2CH₃COOHAcetic acid + K₂CO₃Potassium carbonate

Reaction of magnesium hydrogencarbonate and potassium acetate: Mg(HCO₃)₂Magnesium hydrogencarbonate + CH₃COOKPotassium acetate
💧
⟶
MgCO₃↓Magnesium carbonate + KHCO₃Potassium hydrogencarbonate + CH₃COOHAcetic acid

Electrolysis of aqueous solution

Electrolysis of aqueous potassium acetate yields a variety of products.

Electrolysis of aqueous potassium acetate with water as oxidizing agent ◆ Δ_rG 19.67 kJ/mol K 0.36 × 10⁻³ pK 3.45: CH₃COOKPotassium acetate + H₂OWater
💧⚡
⟶
KHCO₃Potassium hydrogencarbonate + CCarbon + 2H₂↑Hydrogen

Electrolysis of aqueous potassium acetate with water as oxidizing agent ◆ Δ_rG 99.57 kJ/mol K 0.36 × 10⁻¹⁷ pK 17.44: CH₃COOKPotassium acetate + 3H₂OWater
💧⚡
⟶
KHCO₃Potassium hydrogencarbonate + CO₂↑Carbon dioxide + 4H₂↑Hydrogen

Electrolysis of water ◆ Δ_rG 474.258 kJ/mol K 0.82 × 10⁻⁸³ pK 83.09: 2H₂OWater
⚡
⟶
2H₂↑Hydrogen + O₂↑Oxygen

Electrolysis of aqueous potassium acetate with water as non-redox agent ◆ Δ_rG −31.05 kJ/mol K 2.75 × 10⁵ pK −5.44: CH₃COOKPotassium acetate + H₂OWater
💧⚡
⟶
KHCO₃Potassium hydrogencarbonate + CH₄↑Methane

Electrolysis of aqueous potassium acetate with water as non-redox agent ◆ Δ_rG 0.75 kJ/mol K 0.74 × 10⁰ pK 0.13: 2CH₃COOKPotassium acetate + H₂OWater
💧⚡
⟶
K₂CO₃Potassium carbonate + CH₃COOHAcetic acid + CH₄↑Methane

Molten salt electrolysis

Molten salt electrolysis of potassium acetate yields a variety of products.

Molten salt electrolysis of potassium acetate ◆ Δ_rG 756.49 kJ/mol K 0.29 × 10⁻¹³² pK 132.53: 2CH₃COOKPotassium acetate
🔥⚡
⟶
2KPotassium + 4CO↑Carbon monoxide + 3H₂↑Hydrogen

Molten salt electrolysis of potassium acetate ◆ Δ_rG 271.7 kJ/mol K 0.25 × 10⁻⁴⁷ pK 47.60: 2CH₃COOKPotassium acetate
🔥⚡
⟶
K₂OPotassium oxide + 3H₂OWater + 4CCarbon

Decomposition

Decomposition of potassium acetate yields a variety of products.

Decomposition of potassium acetate ◆ Δ_rG −25.05 kJ/mol K 2.45 × 10⁴ pK −4.39: CH₃COOKPotassium acetate
🔥
⟶
KOHPotassium hydroxide + H₂OWater + 2CCarbon

Decomposition of potassium acetate ◆ Δ_rG 27.70 kJ/mol K 0.14 × 10⁻⁴ pK 4.85: 2CH₃COOKPotassium acetate
🔥
⟶
2KOHPotassium hydroxide + CH₃COOHAcetic acid + 2CCarbon

References

List of references

1
James G. Speight (2017)
Lange's Handbook of Chemistry, 17th edition
https://www.accessengineeringlibrary.com/content/book/9781259586095
McGraw Hill Education
- Amazon
Citation list
- ^ Density, 1.57 g/cm³ - p.57
- ^ Melting point, 292 °C - p.57
- ^ Boiling point, Decompose - p.57
- ^ Enthalpy of fusion, 7.65 kJ · mol⁻¹ - p.6-159
- ^ Solubility in Water (g/100 g), See the table - p.339
2
John R. Rumble Jr, David R. Lide, Thomas J. Bruno (2019)
CRC Handbook of Chemistry and Physics 100th Edition
https://www.routledge.com/CRC-Handbook-of-Chemistry-and-Physics/book-series/CRCHANCHEPHY
CRC Press
- Amazon
Citation list
- ^ Density, 1.57 g/cm³ - p.4-48
- ^ Melting point, 309 °C - p.4-48
3
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)
Citation list
4
Atherton Seidell (1919)
Solubilities of Inorganic and Organic Compounds: A Compilation of Quantitative Solubility Data From the Periodical Literature
D. Van Nostrand Company
- Amazon
Citation list
- ^ Solubility in Water (g/100 g), See the table - p.500
- ^ Solubility in Water (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500
- ^ Solubility in Ethanol (g/100 g), See the table - p.500

Δ_rG	−79.90 kJ/mol
K	9.95 × 10¹³
pK	−14.00

Δ_rG	−481.6 kJ/mol
K	2.36 × 10⁸⁴
pK	−84.37

Δ_rG	−17.05 kJ/mol
K	9.71 × 10²
pK	−2.99

Δ_rG	−113.3 kJ/mol
K	7.07 × 10¹⁹
pK	−19.85

Potassium acetate

Names

List of substance names

Formulae and structures

List of formulae

Properties

List of substance properties

Constituents

Constituent ions

Constituent atoms

Ratio of atoms

Thermodynamic properties

Phase transition properties

Standard thermodynamic properties

Solubility

Qualitative solubility

Solubility in water (g/100 g)[1]

Solubility in water (g/100 g)[4]

Solubility in water (g/100 g)[4]

Solubility in ethanol (g/100 g, 20%)[4]

Solubility in ethanol (g/100 g, 40%)[4]

Solubility in ethanol (g/100 g, 50%)[4]

Solubility in ethanol (g/100 g, 60%)[4]

Solubility in ethanol (g/100 g, 70%)[4]

Solubility in ethanol (g/100 g, 80%)[4]

Solubility in ethanol (g/100 g, 90%)[4]

Solubility in ethanol (g/100 g, 95%)[4]

Solubility in ethanol (g/100 g)[4]

Solubility curve (g/100 g)

Preparations

Reaction of acid and base

Reaction of basic oxide and acid

Reaction of salt of weak base and strong base

Reaction of active metal and acid

Reaction of nonmetal, base, and water

Chemical reactions

Electrolytic dissociation

Reaction with strong acid

Reaction with nonvolatile acid

Reaction with oxidizing species

Reaction with reducible species

Reaction with reducing species

Reaction with oxidizable species under acidic condition

Precipitation reaction

Electrolysis of aqueous solution

Molten salt electrolysis

Decomposition

References

List of references

Related substances

Acetate of alkali metal

Carbon oxoacid salt of potassium

Acid

Base and basic oxide

Carboxylate

Related categories

Solubility in water (g/100 g)^[1]

Solubility in water (g/100 g)^[4]

Solubility in water (g/100 g)^[4]

Solubility in ethanol (g/100 g, 20%)^[4]

Solubility in ethanol (g/100 g, 40%)^[4]

Solubility in ethanol (g/100 g, 50%)^[4]

Solubility in ethanol (g/100 g, 60%)^[4]

Solubility in ethanol (g/100 g, 70%)^[4]

Solubility in ethanol (g/100 g, 80%)^[4]

Solubility in ethanol (g/100 g, 90%)^[4]

Solubility in ethanol (g/100 g, 95%)^[4]

Solubility in ethanol (g/100 g)^[4]