Sodium bismuthate
| Names | |
|---|---|
| IUPAC name
Sodium bismuthate
| |
| Other names
Sodium bismuth oxide
Sodium bismuth trioxide | |
| Properties | |
| NaBiO3 | |
| Molar mass | 279.968 g/mol |
| Appearance | Yellow to yellowish-brown powder |
| Odor | Odorless |
| Density | 6.50 g/cm3 |
| Insoluble in cold water Reacts with hot water | |
| Solubility | Reacts with acids Insoluble in most solvents |
| Vapor pressure | ~0 mmHg |
| Thermochemistry | |
| Std enthalpy of
formation (ΔfH |
-686 kJ/mol[1] |
| Hazards | |
| Safety data sheet | Sifma-Aldrich (80%) |
| Flash point | Non-flammable |
| Lethal dose or concentration (LD, LC): | |
| LD50 (Median dose)
|
420 mg/kg (rat, oral) |
| Related compounds | |
| Related compounds
|
Potassium bismuthate |
| Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |
| Infobox references | |
Sodium bismuthate is an inorganic chemical compound, a strong oxidizer with chemical formula NaBiO3.
The compound is rarely available pure, and commercial samples may also contain a mixture of bismuth trioxide, sodium carbonate and sodium peroxide. A related compound with the approximate formula Na3BiO4 also exists.
Contents
Properties
Chemical
Sodium bismuthate is sensitive to moisture and will slowly decompose upon contact.[2]
- 2 NaBiO3 + H2O → 2 NaOH + Bi2O3 + O2
In contact with a haloacid it will release its respective halogen. For example, reaction with hydrochloric acid will produce chlorine gas:
- NaBiO3 + 6 HCl → NaCl + BiCl3 + Cl2
This reaction is similar to the reaction between potassium permanganate with HCl.
Sodium bismuthate is a very strong oxidizer, capable of converting almost any manganese compound to permanganate. The reaction takes place in a hot solution of sulfuric acid or nitric acid.
- 2 Mn2+ + 5 NaBiO3 + 14 H+ → 2 MnO4− + 5 Bi3+ + 5 Na+ + 7 H2O
Sodium bismuthate can perform oxidative 1,2-cleavage on glycols, ketols and alpha hydroxy acids with no further oxidation of the (possible) aldehyde products. These cleavages can be done in the presence of acetic or phosphoric acid at room temperature. Alcohols like methanol or ethanol can be used as the reaction media, as they are oxidized slowly with sodium bismuthate.
Physical
Sodium bismuthate is a yellow-brown powdered solid, insoluble in cold water and decomposes in hot water.
Availability
Sodium bismuthate is sold by chemical suppliers.
Preparation
First, a suspension of bismuth trioxide in a boiling aq. sodium hydroxide is created. Liquid bromine is added to this hot suspension, which yields sodium bismuthate.[3]
- Bi2O3 + 6 NaOH + 2 Br2 → 2 NaBiO3 + 4 NaBr + 3 H2O
The solution in then cooled, to slow the decomposition of the compound. As sodium bismuthate is poorly soluble in water, the resulting product can be easily filtered off.
Another convenient route involves oxidizing bismuth(III) nitrate with sodium persulfate and neutralizing the solution with sodium hydroxide.[4]
A water-free synthesis route involves oxidizing a molten mixture of sodium oxide and bismuth(III) oxide with air (as the source of O2):[5]
- Na2O + Bi2O3 + O2 → 2 NaBiO3
The procedure is analogous to the oxidation of manganese dioxide in alkali to give sodium manganate.
Projects
- Oxidizing agent
- Test for manganese
- Make permanganate
- Compound collecting
- Separation of actinides (Am, Pu, etc.)
Handling
Safety
NaBiO3 is a irritant if inhaled. Continued absorption of NaBiO3 into body causes permanent kidney damage.
Storage
In closed plastic or glass bottles, away from moisture and acids.
Disposal
Can be neutralized by exposure to hot water or hydrogen peroxide and the bismuth recycled.
References
- ↑ Kasenov; Zhambekov; Kasenova; Russian Journal of Physical Chemistry; vol. 71; nb. 6; (1997); p. 1024 - 1026
- ↑ The Merck index (12th ed.). Chapman & Hall Electronic Pub. Division. 2000. p. 1357
- ↑ The Handbook of Preparative Inorganic Chemistry, edited by Georg Brauer. Volume 1 page 627-628
- ↑ https://www.youtube.com/watch?v=wMPYGLEqqoc
- ↑ Greenwood NN (1997). Chemistry of the elements (2nd ed.). Butterworth-Heinemann. p. 578
