Potassium acetate

Potassium acetate (also known as potassium ethanoate) is a potassium salt of acetic acid. It is made when acetic acid reacts with basic potassium compounds like potassium hydroxide, potassium carbonate, or potassium bicarbonate. The chemical formula is CH₃COOK. It is an ionic compound made of potassium ions and acetate ions.

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
ECHA InfoCard	100.004.385
E number	E261 (preservatives)
PubChem CID	31371
UNII	M911911U02 Y
CompTox Dashboard (EPA)	DTXSID7027043
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] 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)[2]
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)[1]
Solubility in ethanol	16.3 g/100 g[1]
Solubility in sulfur dioxide	0.06 g/kg (0 °C)[1]
Acidity (pKa)	4.76
Structure
Crystal structure	Monoclinic
Thermochemistry
Std enthalpy of formation ΔfHo298	−722.6 kJ/mol[1]
Standard molar entropy So298	150.82 J/mol·K[3]
Specific heat capacity, C	109.38 J/mol·K[3]
Pharmacology
ATC code	B05XA17 (WHO)
Hazards
NFPA 704	1 1 0
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

It can dissolve in water, methanol, ethanol or liquid ammonia, but not in ether or acetone, and slightly soluble in sulfur dioxide (0.06g/kg) at 0 °C (32 °F). It is used as a food additive to regulate the acidity of foods.