Potassium acetate

Potassium acetate

Names
Other names Potassium salt, E261
Identifiers
CAS Number	127-08-2 Y
3D model (Jmol)	Interactive image
ChEMBL	ChEMBL1201058 N
ChemSpider	29104 N
ECHA InfoCard	100.004.385
E number	E261 (preservatives)
PubChem	31371
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	98.14 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
Specific heat capacity (C)	109.38 J/mol·K
Std molar entropy (So298)	150.82 J/mol·K
Std enthalpy of formation (ΔfHo298)	-722.6 kJ/mol
Pharmacology
ATC code	B05XA17 (WHO)
Hazards
NFPA 704	1 2 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  (what is YN ?)
Infobox references

Potassium acetate (KCH₃COO) is the potassium salt of acetic acid.

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

This sort of reaction is known as an acid-base neutralization reaction. hydrate in water solution (CH₃COOK·1½H₂O) begins to form semihydrate at 41.3 °C. Potassium acetate is the salt that forms along with water as acetic acid and potassium hydroxide are neutralized together.

Conditions/substances to avoid are: moisture, heat, flames, ignition sources, and strong oxidizing agents.

Potassium acetate can be used as a deicer instead of chloride salts such as calcium chloride or magnesium chloride. It offers the advantage of being less aggressive on soils and much less corrosive, and for this reason is preferred for airport runways. It is, however, more expensive. Potassium acetate is also the extinguishing agent used in class K fire extinguishers because of its ability to cool and form a crust over burning oils.

Potassium acetate is used as a food additive 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 and 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.