Sodium iodide

This MedLibrary.org supplementary page on Sodium iodide is provided directly from the open source Wikipedia as a service to our readers. Please see the note below on authorship of this content, as well as the Wikipedia usage guidelines. To search for other content from our encyclopedia supplement, please use the form below:

Sodium iodide
Sodium iodide
Sodium iodide
Identifiers
CAS number [7681-82-5]
RTECS number WB6475000
Properties
Molecular formula NaI
Molar mass 149.89 g/mol
Appearance White solid.
Density 3.67 g/cm³, solid
Melting point

660°C

Boiling point

1304°C

Solubility in water 184 g/100 ml (25°C)
Structure
Coordination
geometry
Octahedral
Hazards
EU classification Irritant (Xi).
NFPA 704
0
2
1
 
R-phrases R36, R38, R42, R43,
R61
S-phrases S26, S36, S37, S39
Flash point Non-flammable.
Related compounds
Other anions Sodium fluoride
Sodium chloride
Sodium bromide
Other cations Lithium iodide
Potassium iodide
Except where noted otherwise, data are given for
materials in their standard state
(at 25 °C, 100 kPa)

Infobox references

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

Contents

Uses

Sodium iodide is commonly used to treat and prevent iodine deficiency.

Sodium iodide is used in polymerase chain reactions, and also (as an acetone solution) in the Finkelstein reaction, for conversion of an alkyl chloride into an alkyl iodide. This relies on the insolubility of sodium chloride in acetone to drive the reaction.

R-Cl + NaI → R-I + NaCl

Sodium iodide crystals doped with thallium, NaI(Tl), when subjected to ionizing radiation, emit photons (i.e., scintillate) and are used in scintillation detectors, traditionally in nuclear medicine, geophysics, nuclear physics, and environmental measurements. NaI(Tl) is the most widely used scintillation material and has the highest light output. 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.

Solubility data

Solubility of NaI in various solvents
(g NaI / 100g of solvent at 25°C)
H2O 184
Liquid ammonia 162
Liquid sulfur dioxide 15
Methanol 62.5 - 83.0
Formic acid 61.8
Acetonitrile 24.9
Acetone 28.0
Formamide 57 - 85
Acetamide 32.3
Dimethylformamide 3.7 - 6.4
[1]

References

  1. ^ Burgess, J. "Metal Ions in Solution" (Ellis Horwood, New York, 1978) ISBN 0-85312-027-7

See also

External links

Wikipedia content modification information:

  • This page was last modified on 9 October 2008, at 15:55.

Wikipedia Authorship and Review

Wikipedia content provided here is not reviewed directly by MedLibrary.org. Wikipedia content is authored by an open community of volunteers and is not produced by or in any way affiliated with MedLibrary.org.

Wikipedia Usage Guidelines

This article is licensed under the GNU Free Documentation License. It uses material from the Wikipedia article on "Sodium iodide".

The URL for this specific entry is:

All Wikipedia text is available under the terms of the GNU Free Documentation License. (See Copyrights for details). Wikipedia® is a registered trademark of the Wikimedia Foundation, Inc.