Potassium iodide is an inorganic compound with the chemical formula KI. This white salt is the most commercially significant iodide compound, with approximately 37,000 tons produced in 1985. It is less hygroscopic (absorbs water less readily) than sodium iodide, making it easier to work with. Potassium iodide occurs naturally in kelp.[1] Kelp’s iodide content can range from 89 µg/g to 8165 µg/g.[2]
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IUPAC name Potassium iodide |
CAS Number | 7681-11-0 |
ChEBI | CHEBI:8346 |
ChEMBL | ChEMBL1141 |
ChemSpider | 4709 |
DrugBank | DB06715 |
Jmol interactive 3D | Image |
KEGG | D01016 |
PubChem | 4875 |
RTECS number | TT2975000 |
UNII | 1C4QK22F9J |
InChI[show] | |
SMILES[show] |
Chemical formula | KI |
Molar mass | 166.0028 g/mol |
Appearance | white crystalline solid |
Density | 3.123 g/cm3 |
Melting point | 681 °C (1,258 °F; 954 K) |
Boiling point | 1,330 °C (2,430 °F; 1,600 K) |
Solubility in water | 128 g/100 ml (0 °C) 140 g/100 mL (20 °C) 176 g/100 mL (60°C) 206 g/100 mL (100°C) |
Solubility | 2 g/100 mL (ethanol) soluble in acetone (1.31 g/100 mL) slightly soluble in ether, ammonia |
Refractive index (nD) | 1.677 |
Viscosity | 1.0227 cP (733 °C) |
Crystal structure | cubic |
Specific heat capacity (C) |
52.73 J/mol K |
Std enthalpy of formation (ΔfHo298) |
-327.6 kJ/mol |
ATC code | R05CA02 S01XA04, V03AB21 |
Safety data sheet | External MSDS |
NFPA 704 |
Other anions | Potassium fluoride Potassium chloride Potassium bromide |
Other cations | Lithium iodide Sodium iodide Rubidium iodide Caesium iodide |