Iridium(III) bromide

Last updated
Iridium(III) bromide
IrBr3 unit cell.png
Crystal structure
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.030.146 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 233-174-3
PubChem CID
  • InChI=1S/3BrH.Ir/h3*1H;/q;;;+3/p-3
    Key: HTFVQFACYFEXPR-UHFFFAOYSA-K
  • Br[Ir](Br)Br
Properties
Br3Ir
Molar mass 431.929 g·mol−1
Appearancedark reddish-brown solid [1]
Density 6.82 g·cm−3 [2]
insoluble [1]
Solubility insoluble in acids and bases [1]
Related compounds
Other anions
Iridium(III) hydroxide
Iridium(III) chloride
Iridium(III) iodide
Other cations
Ruthenium(III) bromide
Rhodium(III) bromide
Osmium(III) bromide
Platinum(III) bromide
Related compounds
 Iridium(II) bromide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).

Iridium(III) bromide is a bromide of iridium(III), with the chemical formula of IrBr3.

Contents

Preparation

Iridium(III) bromide can be formed by reacting iridium(II) bromide and bromine. Its tetrahydrate can be formed by reacting iridium dioxide dihydrate with hydrobromic acid. [1] It can also be formed by the direct reaction of iridium and bromine at 8 atm and 570 °C. [3]

Properties

Iridium(III) bromide is a dark reddish-brown solid that is insoluble soluble in water, acids, and alkalis and decomposes to iridium(II) bromide on heating. [1] It crystallizes in a highly disordered layered structure of aluminum(III) chloride or chromium(III) chloride type, where the monoclinic unit cell contains four formula units. As with rhenium(III) chloride, rhenium(III) bromide, α-iridium(III) chloride and α-ruthenium(III) chloride, the disorder is due to the different stacking of the metal layers. [4] The light olive green tetrahydrate is slightly soluble in water but insoluble in ethanol and ether. When heated to 100 °C, it turns dark brown with release of water and decomposes to iridium and bromine at higher temperatures. [1] It reacts with germanium dibromide in hydrobromic acid solution to form a compound containing Ir-Ge bond, and adding Cs+ to it can separate Cs3[Ir(GeBr3)nBr6−n] (n=1, 2, 3). [5]

Related Research Articles

<span class="mw-page-title-main">Bromine</span> Chemical element, symbol Br and atomic number 35

Bromine is a chemical element with the 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 the Ancient Greek βρῶμος (bromos) meaning "stench", referring to its sharp and pungent smell.

Hydrobromic acid is a strong acid formed by dissolving the diatomic molecule hydrogen bromide (HBr) in water. "Constant boiling" hydrobromic acid is an aqueous solution that distills at 124.3 °C (255.7 °F) and contains 47.6% HBr by mass, which is 8.77 mol/L. Hydrobromic acid has a pKa of −9, making it a stronger acid than hydrochloric acid, but not as strong as hydroiodic acid. Hydrobromic acid is one of the strongest mineral acids known.

<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. Boiling less concentrated solutions releases H2O until the constant-boiling mixture composition is reached.

<span class="mw-page-title-main">Phosphorus tribromide</span> Chemical compound

Phosphorus tribromide is a colourless liquid with the formula PBr3. The liquid fumes in moist air due to hydrolysis and has a penetrating odour. It is used in the laboratory for the conversion of alcohols to alkyl bromides.

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

Iridium(III) chloride is the inorganic compound with the formula IrCl3. The anhydrous compound is relatively rare, but the related hydrate is useful for preparing other iridium compounds. The anhydrous salt is a dark green crystalline solid. More commonly encountered is the trihydrate IrCl3(H2O)3.

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

Ammonium bromide, NH4Br, is the ammonium salt of hydrobromic acid. The chemical crystallizes in colorless prisms, possessing a saline taste; it sublimes on heating and is easily soluble in water. On exposure to air it gradually assumes a yellow color because of the oxidation of traces of bromide (Br−) to bromine (Br2).

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

Gold(III) bromide is a dark-red to black crystalline solid. It has the empirical formula AuBr3, but exists primarily as a dimer with the molecular formula Au2Br6 in which two gold atoms are bridged by two bromine atoms. It is commonly referred to as gold(III) bromide, gold tribromide, and rarely but traditionally auric bromide, and sometimes as digold hexabromide. As is similar with the other gold halides, this compound is unique for being a coordination complex of a group 11 transition metal that is stable in an oxidation state of +3 whereas copper or silver complexes persist in oxidation states of +1 or +2.

Osmium compounds are compounds containing the element osmium (Os). Osmium forms compounds with oxidation states ranging from −2 to +8. The most common oxidation states are +2, +3, +4, and +8. The +8 oxidation state is notable for being the highest attained by any chemical element aside from iridium's +9 and is encountered only in xenon, ruthenium, hassium, iridium, and plutonium. The oxidation states −1 and −2 represented by the two reactive compounds Na
2[Os
4(CO)
13] and Na
2[Os(CO)
4] are used in the synthesis of osmium cluster compounds.

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.

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

Barium bromide is the chemical compound with the formula BaBr2. It is ionic in nature.

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

Cobalt(II) bromide (CoBr2) is an inorganic compound. In its anhydrous form, it is a green solid that is soluble in water, used primarily as a catalyst in some processes.

<span class="mw-page-title-main">Bismuth tribromide</span> Chemical compound

Bismuth tribromide is an inorganic compound of bismuth and bromine with the chemical formula BiBr3.

<span class="mw-page-title-main">Lead compounds</span> Type of compound

Compounds of lead exist with lead in two main oxidation states: +2 and +4. The former is more common. Inorganic lead(IV) compounds are typically strong oxidants or exist only in highly acidic solutions.

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

Molybdenum(III) bromide is the inorganic compound with the formula MoBr3. It is a black solid that is insoluble in most solvents but dissolves in donor solvents such as pyridine.

Samarium(III) bromide is a crystalline compound of one samarium and three bromine atoms with the chemical formula of SmBr3. Samarium(III) bromide is a dark brown powder at room temperature. The compound has a crystal structure isotypic to that of plutonium(III) bromide.

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

Rhodium(III) bromide refers to inorganic compounds of the formula RhBr3(H2O)n where n = 0 or approximately three. Both forms are brown solids. The hydrate is soluble in water and lower alcohols. It is used to prepare rhodium bromide complexes. Rhodium bromides are similar to the chlorides, but have attracted little academic or commercial attention.

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

Rhenium(III) bromide is a chemical compound with the formula Re3Br9. It is a black lustrous crystalline solid. This compound reacts with water to form rhenium(IV) oxide and is isostructural with rhenium(III) chloride.

Rhenium compounds are compounds formed by the transition metal rhenium (Re). Rhenium can form in many oxidation states, and compounds are known for every oxidation state from -3 to +7 except -2, although the oxidation states +7, +6, +4, and +2 are the most common. Rhenium is most available commercially as salts of perrhenate, including sodium and ammonium perrhenates. These are white, water-soluble compounds. Tetrathioperrhenate anion [ReS4]− is possible.

Iridium tetrabromide is a binary inorganic chemical compound of iridium and bromine with the chemical formula IrBr4. This is a salt of iridium metal and hydrobromic acid.

References

  1. 1 2 3 4 5 6 Kandiner, H. J. (2013-09-03). Iridium (in German). Springer-Verlag. ISBN   978-3-662-12128-3.
  2. ↑ Perry, Dale L. (2016-04-19). Handbook of Inorganic Compounds. CRC Press. ISBN   978-1-4398-1462-8.
  3. ↑ Livingstone, Stanley E. (2017-01-31). The Chemistry of Ruthenium, Rhodium, Palladium, Osmium, Iridium and Platinum: Pergamon Texts in Inorganic Chemistry, Volume 25. Elsevier. ISBN   978-1-4831-5840-2.
  4. ↑ Brodersen, K.; Thiele, G.; Ohnsorge, H.; Recke, I.; Moers, F. (1968-07-01). "Die struktur des IrBr3 und über die ursachen der fehlordnungserscheinungen bei den in schichtenstrukturen kristallisierenden edelmetalltrihalogeniden". Journal of the Less Common Metals (in German). 15 (3): 347–354. doi:10.1016/0022-5088(68)90194-X. ISSN   0022-5088.
  5. ↑ Antonov, P. G.; Agapov, I. A.; Manasevich, D. S. Iridium(III) complexation with germanium(II) compounds in aqueous hydrobromic acid solutions (in Russian). Zhurnal Prikladnoi Khimii (Sankt-Peterburg), 1999. 72 (4): 556-559. ISSN: 0044-4618.
This page is based on this Wikipedia article
Text is available under the CC BY-SA 4.0 license; additional terms may apply.
Images, videos and audio are available under their respective licenses.