Sodium iodide

Sodium iodide
Identifiers
CAS number	Y,  13517-06-1 (dihydrate)
PubChem
ChemSpider	Y
UNII	Y
ChEBI	Y
ChEMBL	N
RTECS number	WB6475000
Jmol-3D images	Image 1
SMILES [Na+].[I-]
InChI InChI=1S/HI.Na/h1H;/q;+1/p-1 Y Key: FVAUCKIRQBBSSJ-UHFFFAOYSA-M Y InChI=1/HI.Na/h1H;/q;+1/p-1 Key: FVAUCKIRQBBSSJ-REWHXWOFAL
Properties
Molecular formula	NaI
Molar mass	149.89 g/mol
Appearance	white solid deliquescent
Odor	odorless
Density	3.67 g/cm3
Melting point	661 °C (1,222 °F; 934 K)
Boiling point	1,304 °C (2,379 °F; 1,577 K)
Solubility in water	178.8 g/100 mL (20 °C) 184 g/100 mL (25 °C) 294 g/100 mL (70 °C) 302 g/100 mL (100 °C)
Solubility	soluble in ethanol and acetone (39.9 g/100 mL)
Acidity (pKa)	8-9.5
Refractive index (nD)	1.7745
Structure
Coordination geometry	Octahedral
Thermochemistry
Std molar entropy So298	91 J·mol−1·K−1[1]
Std enthalpy of formation ΔfHo298	−288 kJ·mol−1[1]
Hazards
MSDS	[1]
EU Index	Not listed
Main hazards	Irritant, can harm the unborn child
Flash point	Non-flammable
Related compounds
Other anions	Sodium fluoride Sodium chloride Sodium bromide
Other cations	Lithium iodide Potassium iodide Rubidium iodide Caesium iodide
Except where noted otherwise, data are given for materials in their standard state (at 25 °C (77 °F), 100 kPa)
N   Y/N?)

Sodium iodide is a white, crystalline salt with the chemical formula NaI, and is used in radiation detection, treatment of iodine deficiency, and as a reactant in the Finkelstein reaction.

Production

Sodium iodide is manufactured from the reaction between iodine and sodium hydroxide.

Uses

Food supplement

Sodium iodide, as well as potassium iodide, is commonly used to treat and prevent iodine deficiency. Iodized table salt contains one part sodium or potassium iodide to 100,000 parts of sodium chloride.^[2]

Organic synthesis

Sodium iodide is used in the Finkelstein reaction, for conversion of an alkyl chloride into an alkyl iodide. This method relies on the insolubility of sodium chloride in acetone to drive the reaction:

R-Cl + NaI → R-I + NaCl

Nuclear medicine

Some radioactive iodide salts of sodium, including [¹²⁵I]NaI and [¹³¹I]NaI, have radiopharmaceutical uses, such as in the treatment of thyroid cancer and hyperthyroidism^[3] or as radiolabeling tracers in imaging (see Isotopes of iodine > Radioiodines I-123, I-124, I-125, and I-131 in medicine and biology).

Thallium-doped NaI(Tl) scintillators

Sodium iodide activated with thallium, NaI(Tl), when subjected to ionizing radiation, emits photons (i.e., scintillate) and is used in scintillation detectors, traditionally in nuclear medicine, geophysics, nuclear physics, and environmental measurements. NaI(Tl) is the most widely used scintillation material. The crystals are usually coupled with a photomultiplier tube, in a hermetically sealed assembly, as sodium iodide is hygroscopic. Fine-tuning of some parameters (i.e., radiation hardness, afterglow, transparency) can be achieved by varying the conditions of the crystal growth. Crystals with a higher level of doping are used in X-ray detectors with high spectrometric quality. Sodium iodide can be used both as single crystals and as polycrystals for this purpose. The wavelength of maximum emission is 415 nm.^[4]

Solubility data

See also

• Gamma spectroscopy
• Scintillation counter
• Teratology

References

External links

• International Chemical Safety Card 1009 - Sodium Iodide (Anhydrous)
• Material Safety Data Sheet (MSDS) - Safety data for sodium iodide
• Sodium iodide as medication — Consumer Information

Molecules detected in outer space Molecules Diatomic Aluminium monochloride Aluminium monofluoride Aluminium monoxide Argon hydride Carbon monophosphide Carbon monosulfide Carbon monoxide Carborundum Cyanogen radical Diatomic carbon Fluoromethylidynium Hydrogen chloride Hydrogen fluoride Hydrogen (molecular) Hydroxyl radical Iron(II) oxide Magnesium monohydride cation Methylidyne radical Nitric oxide Nitrogen (molecular) Nitrogen monohydride Nitrogen sulfide Oxygen (molecular) Phosphorus monoxide Phosphorus nitride Potassium chloride Silicon carbide Silicon mononitride Silicon monoxide Silicon monosulfide Sodium chloride Sodium iodide Sulfur monohydride Sulfur monoxide Titanium oxide Triatomic Aluminium hydroxide Aluminium isocyanide Amino radical Carbon dioxide Carbonyl sulfide CCP radical Chloronium Diazenylium Dicarbon monoxide Ethynyl radical Formyl radical Hydrogen cyanide Hydrogen isocyanide (HCN) Hydrogen isocyanide (HNC) Hydrogen sulfide Hydroperoxyl Iron cyanide Isoformyl Magnesium cyanide Magnesium isocyanide Methylene radical N2H+ Nitrous oxide Nitroxyl Ozone Phosphaethyne Potassium cyanide Protonated molecular hydrogen Sodium cyanide Sodium hydroxide Silicon carbonitride c-Silicon dicarbide Silicon naphthalocyanine Sulfur dioxide Thioformyl Thioxoethenylidene Titanium dioxide Tricarbon Water Four atoms Acetylene Ammonia Cyanic acid Cyanoethynyl Cyclopropynylidyne Formaldehyde Fulminic acid HCCN Hydrogen peroxide Hydromagnesium isocyanide Isocyanic acid Isothiocyanic acid Methylene amidogen Methyl radical Propynylidyne Protonated carbon dioxide Protonated hydrogen cyanide Silicon tricarbide Thioformaldehyde Tricarbon monoxide Tricarbon sulfide Thiocyanic acid Five atoms Ammonium Ion Butadiynyl Carbodiimide Cyanamide Cyanoacetylene Cyanoformaldehyde Cyanomethyl Cyclopropenylidene Formic acid Isocyanoacetylene Ketene Methane Methoxy radical Methylenimine Propadienylidene Protonated formaldehyde Protonated formaldehyde Silane Silicon-carbide cluster Six atoms Acetonitrile Cyanobutadiynyl radical E-Cyanomethanimine Cyclopropenone Diacetylene Ethylene Formamide HC4N Ketenimine Methanethiol Methanol Methyl isocyanide Pentynylidyne Propynal Protonated cyanoacetylene Seven atoms Acetaldehyde Acrylonitrile Cyanodiacetylene Ethylene oxide Hexatriynyl radical Methylacetylene Methylamine Vinyl alcohol Eight atoms Acetic acid Aminoacetonitrile Cyanoallene Ethanimine Glycolaldehyde Heptatrienyl radical Hexapentaenylidene Methylcyanoacetylene Methyl formate Propenal Nine atoms Acetamide Cyanohexatriyne Cyanotriacetylene Dimethyl ether Ethanol Methyldiacetylene Octatetraynyl radical Propene Propionitrile Ten atoms or more Acetone Benzene Buckminsterfullerene (C60 fullerene) ("bucky-ball") C70 fullerene Cyanodecapentayne Cyanopentaacetylene Cyanotetra-acetylene Ethylene glycol Ethyl formate Methyl acetate Methyl-cyano-diacetylene Methyltriacetylene Propanal n-Propyl cyanide Deuterated molecules Ammonia Ammonium ion Formaldehyde Formyl radical Heavy water Hydrogen cyanide Hydrogen deuteride Hydrogen isocyanide Methylacetylene N2D+ Trihydrogen cation Unconfirmed Anthracene Dihydroxyacetone Ethyl methyl ether Glycine Graphene H2NCO+ Linear C5 Naphthalene cation Phosphine Pyrene Silylidine Related Abiogenesis Astrobiology Astrochemistry Atomic and molecular astrophysics Chemical formula Circumstellar envelope Cosmic dust Cosmic ray Cosmochemistry Diffuse interstellar band Extraterrestrial life Extraterrestrial liquid water Forbidden mechanism Helium hydride ion Homochirality Intergalactic dust Interplanetary medium Interstellar medium Iron–sulfur world theory Kerogen Life Organic compound Outer space PAH world hypothesis Panspermia Polycyclic aromatic hydrocarbon (PAH) RNA world hypothesis Spectroscopy Tholin Book:Chemistry Category:Astrochemistry Category:Molecules Portal:Astrobiology Portal:Chemistry