Difference between revisions of "Sodium iodide"
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: NaHCO<sub>3</sub> + HI → NaI + H<sub>2</sub>O + CO<sub>2</sub> | : NaHCO<sub>3</sub> + HI → NaI + H<sub>2</sub>O + CO<sub>2</sub> | ||
− | Another route is addition of iodine to [[sodium thiosulfate]]. | + | Another route is addition of [[iodine]] to [[sodium thiosulfate]]. |
− | : Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> + 2 | + | : 2 Na<sub>2</sub>S<sub>2</sub>O<sub>3</sub> + I<sub>2</sub> → 2 NaI + Na<sub>2</sub>S<sub>4</sub>O<sub>6</sub> |
==Projects== | ==Projects== |
Revision as of 19:10, 29 May 2019
Names | |
---|---|
IUPAC name
Sodium iodide
| |
Other names
Sodium monoiodide
| |
Properties | |
NaI | |
Molar mass | 149.89 g/mol |
Appearance | White solid |
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) |
158.7 g/100 ml (0 °C) 184.2 g/100 ml (25 °C) 227.8 g/100 ml (50 °C) 294 g/100 ml (70 °C) 302 g/100 ml (100 °C) | |
Solubility | Reacts with sulfuric acid Soluble in acetone, acetonitrile, ethanol, formamide, formic acid, isopropanol, methanol Slightly soluble in dimethylformamide, liq. sulfur dioxide Insoluble in halocarbons, hydrocarbons |
Solubility in acetamide | 32.3 g/100 g (41.5 °C) |
Solubility in acetone | 50.4425 g/100 g (25 °C) |
Solubility in acetonitrile | 24.9 g/100 g (25 °C) |
Solubility in ammonia | 162 g/100 g (25 °C) |
Solubility in dichloromethane | 0.009 g/100 g (25 °C) |
Vapor pressure | ~0 mmHg |
Thermochemistry | |
Std molar
entropy (S |
91 J·mol−1·K−1 |
Std enthalpy of
formation (ΔfH |
−288 kJ·mol−1 |
Hazards | |
Safety data sheet | Sigma-Aldrich |
Flash point | Non-flammable |
Lethal dose or concentration (LD, LC): | |
LD50 (Median dose)
|
4.340 mg/kg (rat, oral) |
Related compounds | |
Related compounds
|
Potassium iodide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
Infobox references | |
Sodium iodide (NaI) is a chemical compound, a salt formed from sodium and iodine.
Contents
Properties
Chemical
Addition of a strong acid, like sulfuric acid will form hydroiodic acid, which decomposes to liberate elemental iodine.
- 2 NaI + H2SO4 → Na2SO4 + 2 HI
- 2 HI → H2 + I2
Physical
Sodium iodide is a colorless odorless solid, soluble in water.
Availability
Sodium iodide is sold by chemical suppliers.
Preparation
Can be made by neutralizing hydroiodic acid with sodium hydroxide/carbonate/bicarbonate:
- NaOH + HI → NaI + H2O
- Na2CO3 + 2 HI → 2 NaI + H2O + CO2
- NaHCO3 + HI → NaI + H2O + CO2
Another route is addition of iodine to sodium thiosulfate.
- 2 Na2S2O3 + I2 → 2 NaI + Na2S4O6
Projects
- Make hydrogen iodide and hydroiodic acid
- Make elemental iodine
- Finkelstein reaction
Handling
Safety
Sodium iodide has low toxicity.
Storage
Sodium iodide should be kept in closed bottles, plastic or glass.
Disposal
Can be recycled or dumped in trash.