Caesium hydroxide

Last updated
Caesium hydroxide
Cesium hydroxide monohydrate.jpg
Names
Other names
Cesium hydrate
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.040.298 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 244-344-1
PubChem CID
RTECS number
  • FK9800000
UNII
UN number 2682
  • InChI=1S/Cs.H2O/h;1H2/q+1;/p-1 Yes check.svgY
    Key: HUCVOHYBFXVBRW-UHFFFAOYSA-M Yes check.svgY
  • InChI=1/Cs.H2O/h;1H2/q+1;/p-1
    Key: HUCVOHYBFXVBRW-REWHXWOFAG
  • [OH-].[Cs+]
Properties
CsOH
Molar mass 149.912 g/mol
AppearanceWhitish-yellow deliquescent crystals
Density 3.675 g/cm3
Melting point 272 °C (522 °F; 545 K) [1]
300 g/100 mL at 30 °C
Solubility Soluble in ethanol [2]
Acidity (pKa)15.76 [3]
Thermochemistry
69.9 J·mol−1·K−1 [4]
Std molar
entropy
(S298)
104.2 J·K1·mol1
416.2 kJ·mol−1
Hazards
GHS labelling:
GHS-pictogram-acid.svg GHS-pictogram-silhouette.svg
Danger
H302, H314, H361, H373
P201, P202, P260, P264, P270, P280, P281, P301+P312, P301+P330+P331, P303+P361+P353, P304+P340, P305+P351+P338, P308+P313, P310, P314, P321, P330, P363, P405, P501
NFPA 704 (fire diamond)
NFPA 704.svgHealth 3: Short exposure could cause serious temporary or residual injury. E.g. chlorine gasFlammability 0: Will not burn. E.g. waterInstability 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g. calciumSpecial hazard ALK: Alkaline
3
0
1
ALK
Flash point Not flammable
Lethal dose or concentration (LD, LC):
570 mg/kg (oral, rat) [5]
NIOSH (US health exposure limits):
PEL (Permissible)
none [6]
REL (Recommended)
TWA 2 mg/m3 [6]
IDLH (Immediate danger)
N.D. [6]
Safety data sheet (SDS) ICSC 1592
Related compounds
Other anions
Cæsium oxide
Cæsium fluoride
Other cations
Lithium hydroxide
Sodium hydroxide
Potassium hydroxide
Rubidium hydroxide
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Caesium hydroxide is a strong base (pKa= 15.76) containing the highly reactive alkali metal caesium, much like the other alkali metal hydroxides such as sodium hydroxide and potassium hydroxide. It is the strongest of the five alkali metal hydroxides. [7] Fused Caesium hydroxide dissolves glass by attacking silica framework and it has applications in bringing glass samples into a solution for analytical purposes in commercial glass industry and defense waste processing facility. The melting process is carried out in a nickel or zirconium crucible. [8] Caesium hydroxide fusion at 750°C produces complete dissolution of glass pellets. [8]

Due to its high reactivity, caesium hydroxide is extremely hygroscopic. Laboratory caesium hydroxide is typically a hydrate.

It is an anisotropic etchant of silicon, exposing octahedral planes. This technique can form pyramids and regularly shaped etch pits for uses such as Microelectromechanical systems. It is known to have a higher selectivity to etch highly p-doped silicon than the more commonly used potassium hydroxide.

This compound is not commonly used in experiments due to the high extraction cost of caesium and its reactive behaviour. It acts in similar fashion to the compounds rubidium hydroxide and potassium hydroxide, although more reactive.

Related Research Articles

<span class="mw-page-title-main">Alkali metal</span> Group of highly reactive chemical elements

The alkali metals consist of the chemical elements lithium (Li), sodium (Na), potassium (K), rubidium (Rb), caesium (Cs), and francium (Fr). Together with hydrogen they constitute group 1, which lies in the s-block of the periodic table. All alkali metals have their outermost electron in an s-orbital: this shared electron configuration results in their having very similar characteristic properties. Indeed, the alkali metals provide the best example of group trends in properties in the periodic table, with elements exhibiting well-characterised homologous behaviour. This family of elements is also known as the lithium family after its leading element.

<span class="mw-page-title-main">Caesium</span> Chemical element, symbol Cs and atomic number 55

Caesium is a chemical element; it has symbol Cs and atomic number 55. It is a soft, silvery-golden alkali metal with a melting point of 28.5 °C, which makes it one of only five elemental metals that are liquid at or near room temperature. Caesium has physical and chemical properties similar to those of rubidium and potassium. It is pyrophoric and reacts with water even at −116 °C (−177 °F). It is the least electronegative element, with a value of 0.79 on the Pauling scale. It has only one stable isotope, caesium-133. Caesium is mined mostly from pollucite. Caesium-137, a fission product, is extracted from waste produced by nuclear reactors. It has the largest atomic radius of all elements whose radii have been measured or calculated, at about 260 picometers.

<span class="mw-page-title-main">Rubidium</span> Chemical element, symbol Rb and atomic number 37

Rubidium is a chemical element; it has symbol Rb and atomic number 37. It is a very soft, whitish-grey solid in the alkali metal group, similar to potassium and caesium. Rubidium is the first alkali metal in the group to have a density higher than water. On Earth, natural rubidium comprises two isotopes: 72% is a stable isotope 85Rb, and 28% is slightly radioactive 87Rb, with a half-life of 48.8 billion years—more than three times as long as the estimated age of the universe.

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

Sodium cyanide is a poisonous compound with the formula NaCN. It is a white, water-soluble solid. Cyanide has a high affinity for metals, which leads to the high toxicity of this salt. Its main application, in gold mining, also exploits its high reactivity toward metals. It is a moderately strong base.

<span class="mw-page-title-main">Potassium hydroxide</span> Inorganic compound (KOH)

Potassium hydroxide is an inorganic compound with the formula KOH, and is commonly called caustic potash.

In chemistry, a reactivity series (or reactivity series of elements) is an empirical, calculated, and structurally analytical progression of a series of metals, arranged by their "reactivity" from highest to lowest. It is used to summarize information about the reactions of metals with acids and water, single displacement reactions and the extraction of metals from their ores.

<span class="mw-page-title-main">Cadmium sulfate</span> Chemical compound

Cadmium sulfate is the name of a series of related inorganic compounds with the formula CdSO4·xH2O. The most common form is the monohydrate CdSO4·H2O, but two other forms are known CdSO4·83H2O and the anhydrous salt (CdSO4). All salts are colourless and highly soluble in water.

<span class="mw-page-title-main">Caesium fluoride</span> Chemical compound

Caesium fluoride or cesium fluoride is an inorganic compound with the formula CsF and it is a hygroscopic white salt. Caesium fluoride can be used in organic synthesis as a source of the fluoride anion. Caesium also has the highest electropositivity of all known elements and fluorine has the highest electronegativity of all known elements.

<span class="mw-page-title-main">Potassium peroxide</span> Chemical compound

Potassium peroxide is an inorganic compound with the molecular formula K2O2. It is formed as potassium reacts with oxygen in the air, along with potassium oxide (K2O) and potassium superoxide (KO2).

<span class="mw-page-title-main">Thallium(I) hydroxide</span> Chemical compound

Thallium(I) hydroxide, also called thallous hydroxide, TlOH, is a hydroxide of thallium, with thallium in oxidation state +1.

<span class="mw-page-title-main">Rubidium hydride</span> Chemical compound

Rubidium hydride is the hydride of rubidium. With the formula RbH, it is classified as an alkali metal hydride. It is a white solid and is insoluble in most solvents. It is synthesized by treating rubidium metal with hydrogen. Rubidium hydride is a powerful superbase and reacts violently with water.

<span class="mw-page-title-main">Caesium acetate</span> Chemical compound

Caesium acetate or cesium acetate is an ionic caesium compound with the molecular formula CH3COOCs. It is a white solid that may be formed by the reaction of caesium hydroxide or caesium carbonate with acetic acid.

<span class="mw-page-title-main">Caesium chromate</span> Chemical compound

Caesium chromate or cesium chromate is an inorganic compound with the formula Cs2CrO4. It is a yellow crystalline solid that is the caesium salt of chromic acid, and it crystallises in the orthorhombic system.

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

Copper(II) azide is a medium density explosive with the molecular formula Cu(N3)2.

<span class="mw-page-title-main">Caesium hydride</span> Chemical compound

Caesium hydride or cesium hydride is an inorganic compound of caesium and hydrogen with the chemical formula CsH. It is an alkali metal hydride. It was the first substance to be created by light-induced particle formation in metal vapor, and showed promise in early studies of an ion propulsion system using caesium. It is the most reactive stable alkaline metal hydride of all. It is a powerful superbase and reacts with water extremely vigorously.

<span class="mw-page-title-main">Caesium nitrate</span> Chemical compound CsNO3

Caesium nitrate or cesium nitrate is a salt with the chemical formula Cs N O3. An alkali metal nitrate, it is used in pyrotechnic compositions, as a colorant and an oxidizer, e.g. in decoys and illumination flares. The caesium emissions are chiefly due to two powerful spectral lines at 852.113 nm and 894.347 nm.

<span class="mw-page-title-main">Cadmium cyanide</span> Chemical compound

Cadmium cyanide is an inorganic compound with the formula Cd(CN)2. It is a white crystalline compound that is used in electroplating. It is very toxic, along with other cadmium and cyanide compounds.

<span class="mw-page-title-main">Caesium sulfate</span> Chemical compound

Caesium sulfate or cesium sulfate is the inorganic compound and salt with the formula Cs2SO4. It is a white water-soluble solid that is used to prepare dense aqueous solutions for use in isopycnic (or "density-gradient") centrifugation. It is isostructural with potassium salt.

<span class="mw-page-title-main">4-Methyl-2-pentanol</span> Chemical compound

4-Methyl-2-pentanol or methyl isobutyl carbinol (MIBC) is an organic chemical compound used primarily as a frother in mineral flotation and in the production of lubricant oil additives such as Zinc dithiophosphate. It is also used as a solvent, in organic synthesis, and in the manufacture of brake fluid and as a precursor to some plasticizers. It is an acetone derivative in liquid state, with limited solubility in water but generally miscible with most organic solvents.

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

Copper(II) tetrafluoroborate is any inorganic compound with the formula Cu(H2O)x(BF4)2. As usually encountered, it is assumed to be the hexahydrate (x = 6), but this salt can be partially dehydrated to the tetrahydrate. Regardless, these compounds are aquo complexes of copper in its +2 oxidation state, with two weakly coordinating tetrafluoroborate anions.

References

  1. "ICSC 1592 - Cesium Hydroxide".
  2. Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, Florida: CRC Press, pp. 4–51, ISBN   0-8493-0594-2
  3. "Sortierte Liste: pKb-Werte, nach Ordnungszahl sortiert. – Das Periodensystem online".
  4. Lide, David R. (1998), Handbook of Chemistry and Physics (87 ed.), Boca Raton, Florida: CRC Press, pp. 5–14, ISBN   0-8493-0594-2
  5. Gigiena Truda i Professional'nye Zabolevaniya. Labor Hygiene and Occupational Diseases., 21(1)(29), 1977
  6. 1 2 3 NIOSH Pocket Guide to Chemical Hazards. "#0111". National Institute for Occupational Safety and Health (NIOSH).
  7. Considine, Douglas M.; Considine, Glenn D. (2013-12-11). Van Nostrand's Scientific Encyclopedia. Springer Science & Business Media. ISBN   978-1-4757-6918-0.
  8. 1 2 Coleman, C.J; Spencer, W.A. (April 1998). "CsOH is a very strong base that attacks the silica framework of glass under fusion conditions. Cesium Hydroxide Fusion Dissolution of Analytical Reference Glass-1 in Both Powder and Shard Form" (PDF). Westinghouse Savannah River Company. CsOH is a very strong base that attacks the silica framework of glass under fusion conditions.