Sodium bromide

Last updated
Sodium bromide
Sodium-bromide-3D-ionic.png
Sodium bromide.jpg
Names
IUPAC name
Sodium bromide
Identifiers
3D model (JSmol)
ChEMBL
ChemSpider
ECHA InfoCard 100.028.727 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
RTECS number
  • anhydrous:VZ3150000
UNII
  • InChI=1S/BrH.Na/h1H;/q;+1/p-1 Yes check.svgY
    Key: JHJLBTNAGRQEKS-UHFFFAOYSA-M Yes check.svgY
  • anhydrous:InChI=1/BrH.Na/h1H;/q;+1/p-1
    Key: JHJLBTNAGRQEKS-REWHXWOFAR
  • anhydrous:[Na+].[Br-]
Properties
NaBr
Molar mass 102.894 g·mol−1
AppearanceWhite powder, hygroscopic
Density 3.21 g/cm3 (anhydrous)
2.18 g/cm3 (dihydrate)
Melting point 747 °C (1,377 °F; 1,020 K)
(anhydrous)
36 °C (97 °F; 309 K)
(dihydrate) decomposes [1]
Boiling point 1,390 °C (2,530 °F; 1,660 K) [1]
71.35 g/100 mL (−20 °C)
79.52 g/100 mL (0 °C)
94.32 g/100 mL (25 °C) [2]
104.9 g/100 mL (40 °C)
116.2 g/100 mL (100 °C) [3]
Solubility Soluble in alcohol, liquid ammonia, pyridine, hydrazine, SO2
Insoluble in acetone, acetonitrile [2]
Solubility in methanol 17.3 g/100 g (0 °C)
16.8 g/100 g (20 °C)
16.1 g/100 g (40 °C)
15.3 g/100 g (60 °C) [2]
Solubility in ethanol 2.45 g/100 g (0 °C)
2.32 g/100 g (20 °C)
2.29 g/100 g (30 °C)
2.35 g/100 g (70 °C) [2]
Solubility in formic acid 19.3 g/100 g (18 °C)
19.4 g/100 g (25 °C) [2]
Solubility in glycerol 38.7 g/100 g (20 °C) [2]
Solubility in dimethylformamide 3.2 g/100 g (10.3 °C) [2]
Vapor pressure 1 torr (806 °C)
5 torr (903 °C) [1]
41.0·10−6 cm3/mol
Thermal conductivity 5.6 W/(m·K) (150 K) [4]
1.6428 (24 °C)
n KrF = 1.8467 (24 °C)
n He–Ne = 1.6389 (24 °C) [5]
Viscosity 1.42 cP (762 °C)
1.08 cP (857 °C)
0.96 cP (937 °C) [2]
Structure
Cubic
a = 5.97 Å [4]
Thermochemistry
51.4 J/(mol·K) [2]
Std molar
entropy
(S298)
86.82 J/(mol·K) [2]
−361.41 kJ/mol [2]
−349.3 kJ/mol [2]
Pharmacology
Legal status
  • AU: S4 (Prescription only)/S5
Hazards
NFPA 704 (fire diamond)
[6]
NFPA 704.svgHealth 2: Intense or continued but not chronic exposure could cause temporary incapacitation or possible residual injury. E.g. chloroformFlammability 0: Will not burn. E.g. waterInstability 0: Normally stable, even under fire exposure conditions, and is not reactive with water. E.g. liquid nitrogenSpecial hazards (white): no code
2
0
0
Flash point 800 °C (1,470 °F; 1,070 K)
Lethal dose or concentration (LD, LC):
3500 mg/kg (rats, oral)
Safety data sheet (SDS) External MSDS
Related compounds
Other anions
Other cations
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
X mark.svgN  verify  (what is  Yes check.svgYX mark.svgN ?)

Sodium bromide is an inorganic compound with the formula Na Br . It is a high-melting white, crystalline solid that resembles sodium chloride. It is a widely used source of the bromide ion and has many applications. [7]

Contents

Synthesis, structure, reactions

NaBr crystallizes in the same cubic motif as NaCl, NaF and NaI. The anhydrous salt crystallizes above 50.7 °C. [7] Dihydrate salt (NaBr·2H2O) crystallize out of water solution below 50.7 °C. [8]

NaBr is produced by treating sodium hydroxide with hydrogen bromide.

Sodium bromide can be used as a source of the chemical element bromine. This can be accomplished by treating an aqueous solution of NaBr with chlorine gas:

2 NaBr + Cl2 → Br2 + 2 NaCl

Applications

Sodium bromide is the most useful inorganic bromide in industry. [7] It is also used as a catalyst in TEMPO-mediated oxidation reactions. [9]

Medicine

Bromo-Seltzer newspaper ad (1908) Bromo seltzer newspaper.png
Bromo-Seltzer newspaper ad (1908)

Also known as Sedoneural, sodium bromide has been used as a hypnotic, anticonvulsant, and sedative in medicine, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries. Its action is due to the bromide ion, and for this reason potassium bromide is equally effective. In 1975, bromides were removed from drugs in the U.S. such as Bromo-Seltzer due to toxicity. [10]

Preparation of other bromine compounds

Sodium bromide is widely used for the preparation of other bromides in organic synthesis and other areas. It is a source of the bromide nucleophile to convert alkyl chlorides to more reactive alkyl bromides by the Finkelstein reaction:

NaBr + RCl → RBr + NaCl (R = alkyl)

Once a large need in photography, but now shrinking, the photosensitive salt silver bromide is prepared using NaBr.

Disinfectant

Sodium bromide is used in conjunction with chlorine as a disinfectant for hot tubs and swimming pools.

Petroleum industry

Because of its high solubility in water (943.2 g/L or 9.16 mol/L, at 25 °C) sodium bromide is used to prepare dense drilling fluids used in oil wells to compensate a possible overpressure arising in the fluid column and to counteract the associated trend to blow out. The presence of the sodium cation also causes the bentonite added to the drilling fluid to swell, while the high ionic strength induces bentonite flocculation.

Safety

NaBr has a very low toxicity with an oral LD50 estimated at 3.5 g/kg for rats. [6] However, this is a single-dose value. Bromide ion is a cumulative toxin with a relatively long half-life (in excess of a week in humans): see potassium bromide.

Related Research Articles

<span class="mw-page-title-main">Bromine</span> Chemical element with atomic number 35 (Br)

Bromine is a chemical element; it has symbol Br and atomic number 35. It is a volatile red-brown liquid at room temperature that evaporates readily to form a similarly coloured vapour. Its properties are intermediate between those of chlorine and iodine. Isolated independently by two chemists, Carl Jacob Löwig and Antoine Jérôme Balard, its name was derived from Ancient Greek βρῶμος (bromos) 'stench', referring to its sharp and pungent smell.

<span class="mw-page-title-main">Chlorine</span> Chemical element with atomic number 17 (Cl)

Chlorine is a chemical element; it has symbol Cl and atomic number 17. The second-lightest of the halogens, it appears between fluorine and bromine in the periodic table and its properties are mostly intermediate between them. Chlorine is a yellow-green gas at room temperature. It is an extremely reactive element and a strong oxidising agent: among the elements, it has the highest electron affinity and the third-highest electronegativity on the revised Pauling scale, behind only oxygen and fluorine.

<span class="mw-page-title-main">Halogen</span> Group of chemical elements

The halogens are a group in the periodic table consisting of six chemically related elements: fluorine (F), chlorine (Cl), bromine (Br), iodine (I), and the radioactive elements astatine (At) and tennessine (Ts), though some authors would exclude tennessine as its chemistry is unknown and is theoretically expected to be more like that of gallium. In the modern IUPAC nomenclature, this group is known as group 17.

<span class="mw-page-title-main">Haloalkane</span> Group of chemical compounds derived from alkanes containing one or more halogens

The haloalkanes are alkanes containing one or more halogen substituents. They are a subset of the general class of halocarbons, although the distinction is not often made. Haloalkanes are widely used commercially. They are used as flame retardants, fire extinguishants, refrigerants, propellants, solvents, and pharmaceuticals. Subsequent to the widespread use in commerce, many halocarbons have also been shown to be serious pollutants and toxins. For example, the chlorofluorocarbons have been shown to lead to ozone depletion. Methyl bromide is a controversial fumigant. Only haloalkanes that contain chlorine, bromine, and iodine are a threat to the ozone layer, but fluorinated volatile haloalkanes in theory may have activity as greenhouse gases. Methyl iodide, a naturally occurring substance, however, does not have ozone-depleting properties and the United States Environmental Protection Agency has designated the compound a non-ozone layer depleter. For more information, see Halomethane. Haloalkane or alkyl halides are the compounds which have the general formula "RX" where R is an alkyl or substituted alkyl group and X is a halogen.

<span class="mw-page-title-main">Potassium chloride</span> Ionic compound (KCl)

Potassium chloride is a metal halide salt composed of potassium and chlorine. It is odorless and has a white or colorless vitreous crystal appearance. The solid dissolves readily in water, and its solutions have a salt-like taste. Potassium chloride can be obtained from ancient dried lake deposits. KCl is used as a fertilizer, in medicine, in scientific applications, domestic water softeners, and in food processing, where it may be known as E number additive E508.

<span class="mw-page-title-main">Sodium hypochlorite</span> Chemical compound (known in solution as bleach)

Sodium hypochlorite is an alkaline inorganic chemical compound with the formula NaOCl. It is commonly known in a dilute aqueous solution as bleach or chlorine bleach. It is the sodium salt of hypochlorous acid, consisting of sodium cations and hypochlorite anions.

<span class="mw-page-title-main">Potassium bromide</span> Ionic compound (KBr)

Potassium bromide (KBr) is a salt, widely used as an anticonvulsant and a sedative in the late 19th and early 20th centuries, with over-the-counter use extending to 1975 in the US. Its action is due to the bromide ion. Potassium bromide is used as a veterinary drug, in antiepileptic medication for dogs.

<span class="mw-page-title-main">Hydrogen bromide</span> Chemical compound

Hydrogen bromide is the inorganic compound with the formula HBr. It is a hydrogen halide consisting of hydrogen and bromine. A colorless gas, it dissolves in water, forming hydrobromic acid, which is saturated at 68.85% HBr by weight at room temperature. Aqueous solutions that are 47.6% HBr by mass form a constant-boiling azeotrope mixture that boils at 124.3 °C (255.7 °F). Boiling less concentrated solutions releases H2O until the constant-boiling mixture composition is reached.

<span class="mw-page-title-main">Phosphonium</span> Family of polyatomic cations containing phosphorus

In chemistry, the term phosphonium describes polyatomic cations with the chemical formula PR+
4
. These cations have tetrahedral structures. The salts are generally colorless or take the color of the anions.

A bromide ion is the negatively charged form (Br) of the element bromine, a member of the halogens group on the periodic table. Most bromides are colorless. Bromides have many practical roles, being found in anticonvulsants, flame-retardant materials, and cell stains. Although uncommon, chronic toxicity from bromide can result in bromism, a syndrome with multiple neurological symptoms. Bromide toxicity can also cause a type of skin eruption, see potassium bromide. The bromide ion has an ionic radius of 196 pm.

<span class="mw-page-title-main">Bromate</span> Ion, and compounds containing the ion

The bromate anion, BrO
3
, is a bromine-based oxoanion. A bromate is a chemical compound that contains this ion. Examples of bromates include sodium bromate,, and potassium bromate,.

<span class="mw-page-title-main">Sodium dithionate</span> Chemical compound

Sodium dithionate Na2S2O6 is an important compound for inorganic chemistry. It is also known under names disodium dithionate, sodium hyposulfate, and sodium metabisulfate. The sulfur can be considered to be in its +5 oxidation state.

<span class="mw-page-title-main">Sodium bromate</span> Chemical compound

Sodium bromate, the inorganic compound with the chemical formula of NaBrO3, is the sodium salt of bromic acid. It is a strong oxidant.

<span class="mw-page-title-main">Cobalt(III) fluoride</span> Chemical compound

Cobalt(III) fluoride is the inorganic compound with the formula CoF3. Hydrates are also known. The anhydrous compound is a hygroscopic brown solid. It is used to synthesize organofluorine compounds.

<span class="mw-page-title-main">Hypobromite</span> Ion, and compounds containing the ion

The hypobromite ion, also called alkaline bromine water, is BrO. Bromine is in the +1 oxidation state. The Br–O bond length is 1.82 Å. Hypobromite is the bromine compound analogous to hypochlorites found in common bleaches, and in immune cells. In many ways, hypobromite functions in the same manner as hypochlorite, and is also used as a germicide and antiparasitic in both industrial applications, and in the immune system.

Bromine compounds are compounds containing the element bromine (Br). These compounds usually form the -1, +1, +3 and +5 oxidation states. Bromine is intermediate in reactivity between chlorine and iodine, and is one of the most reactive elements. Bond energies to bromine tend to be lower than those to chlorine but higher than those to iodine, and bromine is a weaker oxidising agent than chlorine but a stronger one than iodine. This can be seen from the standard electrode potentials of the X2/X couples (F, +2.866 V; Cl, +1.395 V; Br, +1.087 V; I, +0.615 V; At, approximately +0.3 V). Bromination often leads to higher oxidation states than iodination but lower or equal oxidation states to chlorination. Bromine tends to react with compounds including M–M, M–H, or M–C bonds to form M–Br bonds.

Iodine compounds are compounds containing the element iodine. Iodine can form compounds using multiple oxidation states. Iodine is quite reactive, but it is much less reactive than the other halogens. For example, while chlorine gas will halogenate carbon monoxide, nitric oxide, and sulfur dioxide, iodine will not do so. Furthermore, iodination of metals tends to result in lower oxidation states than chlorination or bromination; for example, rhenium metal reacts with chlorine to form rhenium hexachloride, but with bromine it forms only rhenium pentabromide and iodine can achieve only rhenium tetraiodide. By the same token, however, since iodine has the lowest ionisation energy among the halogens and is the most easily oxidised of them, it has a more significant cationic chemistry and its higher oxidation states are rather more stable than those of bromine and chlorine, for example in iodine heptafluoride.

There are three sets of Indium halides, the trihalides, the monohalides, and several intermediate halides. In the monohalides the oxidation state of indium is +1 and their proper names are indium(I) fluoride, indium(I) chloride, indium(I) bromide and indium(I) iodide.

Organobromine chemistry is the study of the synthesis and properties of organobromine compounds, also called organobromides, which are organic compounds that contain carbon bonded to bromine. The most pervasive is the naturally produced bromomethane.

References

  1. 1 2 3 Pradyot, Patnaik (2003). Handbook of Inorganic Chemicals. The McGraw-Hill Companies, Inc. ISBN   978-0-07-049439-8.
  2. 1 2 3 4 5 6 7 8 9 10 11 12 "Sodium bromide".
  3. Seidell, Atherton; Linke, William F. (1919). Solubilities of Inorganic and Organic Compounds (2nd ed.). D. Van Nostrand Company.
  4. 1 2 "Sodium Bromide (NaBr)". korth.de. Korth Kristalle GmbH. Archived from the original on 2014-07-14. Retrieved 2014-06-11.
  5. Polyanskiy, Mikhail. "Refractive index of NaBr (Sodium bromide) - Li". refractiveindex.info. Retrieved 2014-06-11.
  6. 1 2 "Sodium bromide MSDS". sciencelab.com. Sciencelab.com, Inc. 2013-05-21. Archived from the original (PDF) on 2013-10-07. Retrieved 2014-06-11.
  7. 1 2 3 Michael J. Dagani, Henry J. Barda, Theodore J. Benya, David C. Sanders "Bromine Compounds" in Ullmann's Encyclopedia of Industrial Chemistry Wiley-VCH, Weinheim, 2000. doi : 10.1002/14356007.a04_405
  8. Eagleson, Mary (translated by) (1994). Concise Encyclopedia Chemistry (Illustrated, revised, English language ed.). Berlin [u.a.]: Walter De Gruyter. p. 996. ISBN   9783110114515.
  9. Hirota, Masayuki; Tamura, Naoyuki; Saito, Tsuguyuki; Isogai, Akira (2010). "Water dispersion of cellulose II nanocrystals prepared by TEMPO-mediated oxidation of mercerized cellulose at pH 4.8". Cellulose. 17 (2): 279–288. doi:10.1007/s10570-009-9381-2. S2CID   97264888.
  10. "Bromide: Potassium & Sodium". canine-epilepsy.com. Canine-Epilepsy Resources. 2011-05-31. Archived from the original on 2014-03-06. Retrieved 2014-06-11.