Chemistry:Potassium acetate

Short description: Colourless soluble salt of acetic acid

Potassium acetate

Names
Preferred IUPAC name Potassium acetate
Other names Potassium ethanoate, E261
Identifiers
CAS Number	127-08-2 Y
3D model (JSmol)	Interactive image
ChEMBL	ChEMBL1201058 N
ChemSpider	29104 N
PubChem CID	31371
UNII	M911911U02 Y
InChI InChI=1S/C2H4O2.K/c1-2(3)4;/h1H3,(H,3,4);/q;+1/p-1 N Key: SCVFZCLFOSHCOH-UHFFFAOYSA-M N InChI=1/C2H4O2.K/c1-2(3)4;/h1H3,(H,3,4);/q;+1/p-1 Key: SCVFZCLFOSHCOH-REWHXWOFAA
SMILES CC(=O)[O-].[K+]
Properties
Chemical formula	C2H3KO2
Molar mass	98.142 g·mol−1
Appearance	White deliquescent crystalline powder
Density	1.8 g/cm3 (20 °C) 1.57 g/cm3 (25 °C)
Melting point	292 °C (558 °F; 565 K)
Boiling point	Decomposes
Solubility in water	216.7 g/100 mL (0.1 °C) 233.8 g/100 mL (10 °C) 268.6 g/100 mL (25 °C) 320.8 g/100 mL (40 °C) 390.7 g/100 mL (96 °C)
Solubility	Soluble in alcohol, liquid ammonia Insoluble in ether, acetone
Solubility in methanol	24.24 g/100 g (15 °C) 53.54 g/100 g (73.4 °C)
Solubility in ethanol	16.3 g/100 g
Solubility in sulfur dioxide	0.06 g/kg (0 °C)
Acidity (pKa)	4.76
Structure
Crystal structure	Monoclinic
Thermochemistry
Heat capacity (C)	109.38 J/mol·K
Std molar entropy (So298)	150.82 J/mol·K
Std enthalpy of formation (ΔfH⦵298)	−722.6 kJ/mol
Pharmacology
1=ATC code }}	B05XA17 (WHO)
Hazards
NFPA 704 (fire diamond)	1 1 0
Lethal dose or concentration (LD, LC):
LD50 (median dose)	3250 mg/kg (oral, rat)
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is YN ?)
Infobox references

Tracking categories (test):

• SizeSet

Potassium acetate (also called potassium ethanoate), (CH₃COOK) is the potassium salt of acetic acid. It is a hygroscopic solid at room temperature.

Preparation

It can be prepared by treating a potassium-containing base such as potassium hydroxide or potassium carbonate with acetic acid:

CH₃COOH + KOH → CH₃COOK + H₂O

This sort of reaction is known as an acid-base neutralization reaction.

The sesquihydrate in water solution (CH₃COOK·1½H₂O) begins to form semihydrate at 41.3 °C.

Applications

Deicing

Potassium acetate (as a substitute for calcium chloride or magnesium chloride) can be used as a deicer to remove ice or prevent its formation. It offers the advantage of being less aggressive on soils and much less corrosive: for this reason, it is preferred for airport runways although it is more expensive.

Fire extinguishing

Potassium acetate is the extinguishing agent used in Class K fire extinguishers because of its ability to cool and form a crust over burning oils.

Food additive

Potassium acetate is used in processed foods as a preservative and acidity regulator. In the European Union, it is labeled by the E number E261; it is also approved for usage in the USA, Australia, and New Zealand. Potassium hydrogen diacetate (CAS #4251-29-0 ) with formula KH(OOCCH₃)₂ is a related food additive with the same E number as potassium acetate.

Medicine and biochemistry

In medicine, potassium acetate is used as part of electrolyte replacement protocols in the treatment of diabetic ketoacidosis because of its ability to break down to bicarbonate to help neutralize the acidotic state.

In molecular biology, potassium acetate is used to precipitate dodecyl sulfate (DS) and DS-bound proteins to extract ethanol from DNA.

Potassium acetate is used in mixtures applied for tissue preservation, fixation, and mummification. Most museums today use a formaldehyde-based method recommended by Kaiserling in 1897 which contains potassium acetate. This process was used to soak Lenin's corpse.

Use in executions

Potassium acetate was incorrectly used in place of potassium chloride when putting a prisoner to death in Oklahoma in January 2015. Charles Frederick Warner was executed on January 15, 2015 with potassium acetate; this was not public knowledge until the scheduled execution of Richard Glossip was called off. In August 2017, the U.S. state of Florida executed Mark James Asay using a combination of etomidate, rocuronium bromide, and potassium acetate. The drug was also used in the February 2023 execution of Donald Dillbeck, once again in combination with etomidate and rocuronium bromide.

Industry

Potassium acetate is used as a catalyst in the production of polyurethanes.

Historical

It is used as a diuretic and urinary alkalizer. Before modern chemistry, it was variously called terra foliata tartari, sal Sennerti, tartarus regeneratus, arcanum tartari and sal diureticus. In 1760 it was used in the preparation of Cadet's fuming liquid ((CH₃)₂As)₂O, the first organometallic compound ever produced.

External links

Acetyl halides and salts of the acetate ion
AcOH																	He
LiOAc	Be(OAc)2 BeAcOH											B(OAc)3	AcOAc ROAc	NH4OAc	AcOOH	FAc	Ne
NaOAc	Mg(OAc)2											Al(OAc)3 ALSOL Al(OAc)2OH Al2SO4(OAc)4	Si	P	S	ClAc	Ar
KOAc	Ca(OAc)2	Sc(OAc)3	Ti(OAc)4	VO(OAc)3	Cr(OAc)2 Cr(OAc)3	Mn(OAc)2 Mn(OAc)3	Fe(OAc)2 Fe(OAc)3	Co(OAc)2, Co(OAc)3	Ni(OAc)2	Cu(OAc)2	Zn(OAc)2	Ga(OAc)3	Ge	As(OAc)3	Se	BrAc	Kr
RbOAc	Sr(OAc)2	Y(OAc)3	Zr(OAc)4	Nb	Mo(OAc)2	Tc	Ru(OAc)2 Ru(OAc)3 Ru(OAc)4	Rh2(OAc)4	Pd(OAc)2	AgOAc	Cd(OAc)2	In	Sn(OAc)2 Sn(OAc)4	Sb(OAc)3	Te	IAc	Xe
CsOAc	Ba(OAc)2		Hf	Ta	W	Re	Os	Ir	Pt(OAc)2	Au	Hg2(OAc)2, Hg(OAc)2	TlOAc Tl(OAc)3	Pb(OAc)2 Pb(OAc)4	Bi(OAc)3	Po	At	Rn
Fr	Ra		Rf	Db	Sg	Bh	Hs	Mt	Ds	Rg	Cn	Nh	Fl	Mc	Lv	Ts	Og
		↓
		La(OAc)3	Ce(OAc)x	Pr	Nd	Pm	Sm(OAc)3	Eu(OAc)3	Gd(OAc)3	Tb	Dy(OAc)3	Ho(OAc)3	Er	Tm	Yb(OAc)3	Lu(OAc)3
		Ac	Th	Pa	UO2(OAc)2	Np	Pu	Am	Cm	Bk	Cf	Es	Fm	Md	No	Lr