Copper benzoate

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Copper benzoate
(Cuaq4O2CPh)PhCO2.svg
Copper benzoate.jpg
Copper benzoate picture.jpg
Names
IUPAC name
copper dibenzoate
Other names
cupric benzoate
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.007.776 OOjs UI icon edit-ltr-progressive.svg
PubChem CID
UNII
  • InChI=1S/2C7H6O2.Cu/c2*8-7(9)6-4-2-1-3-5-6;/h2*1-5H,(H,8,9);/q;;+2/p-2 Yes check.svgY
    Key: YEOCHZFPBYUXMC-UHFFFAOYSA-L Yes check.svgY
  • InChI=1/2C7H6O2.Cu/c2*8-7(9)6-4-2-1-3-5-6;/h2*1-5H,(H,8,9);/q;;+2/p-2
    Key: YEOCHZFPBYUXMC-NUQVWONBAX
  • [Cu+2].[O-]C(=O)c1ccccc1.[O-]C(=O)c1ccccc1
  • Chinese lantern structure:c0ccccc0[C-](O[Cu+2]123)O[Cu+2](O[C-](O1)c0ccccc0)(O[C-](O2)c0ccccc0)O[C-](O3)c0ccccc0
Properties
C14H10CuO4
Molar mass 305.7728 g/mol
Appearanceblue solid
Density 1.197g/cm3
Hazards
Flash point 111.4 °C (232.5 °F; 384.5 K)
NIOSH (US health exposure limits):
PEL (Permissible)
TWA 1 mg/m3 (as Cu) [1]
REL (Recommended)
TWA 1 mg/m3 (as Cu) [1]
IDLH (Immediate danger)
TWA 100 mg/m3 (as Cu) [1]
Related compounds
Other cations
sodium benzoate
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
Yes check.svgY  verify  (what is  Yes check.svgYX mark.svgN ?)

Copper benzoate is the chemical compounds with the formula Cu(C6H5CO2)2(H2O)x. These coordination complexes are derived from the cupric ion and the conjugate base of benzoic acid. Many derivatives are known with diverse ancillary ligands. This compound has found some use as a source of blue light in fireworks.

Contents

Preparation

In laboratory, copper benzoate can be made by combining aqueous solutions of potassium benzoate with copper sulfate. Hydrated copper benzoate precipitates as a pale blue solid:

4 C6H5CO2K + 2 CuSO4·5H2O → Cu2(C6H5CO2)4(H2O)2 + 2 K2SO4 + 8 H2O

The primary use of this compound is in the production of a blue flame in fireworks. Copper benzoate made from sodium benzoate for use in fireworks may result in strong yellow dilution of the flame unless the precipitate is carefully washed to remove sodium ions (which emit bright yellow). Emission from potassium does not complicate the emission spectrum. [2]

Structure

Structure of one form of copper(II) benzoate. Cu2(PhCO2)4(aq)2.svg
Structure of one form of copper(II) benzoate.

Copper(II) benzoate exists in at least two structural forms, depending on the degree of hydration. As in copper(II) acetate, one form of copper benzoate adopts a "Chinese lantern" structure, [3] wherein a pair of copper centers are linked by four bridging carboxylate ligands. Typically, one site on each copper center is occupied by water, which can be replaced by other ligands. [4] A hydrated form is also known, wherein each Cu(II) centre is bound to four water ligands and a bidentate O,O-benzoate. [5]

Related Research Articles

Benedict's reagent is a chemical reagent and complex mixture of sodium carbonate, sodium citrate, and copper(II) sulfate pentahydrate. It is often used in place of Fehling's solution to detect the presence of reducing sugars. The presence of other reducing substances also gives a positive result. Such tests that use this reagent are called the Benedict's tests. A positive test with Benedict's reagent is shown by a color change from clear blue to brick-red with a precipitate.

<span class="mw-page-title-main">Basic copper carbonate</span> Chemical compound

Basic copper carbonate is a chemical compound, more properly called copper(II) carbonate hydroxide. It can be classified as a coordination polymer or a salt. It consists of copper(II) bonded to carbonate and hydroxide with formula Cu2(CO3)(OH)2. It is a green solid that occurs in nature as the mineral malachite. It has been used since antiquity as a pigment, and it is still used as such in artist paints, sometimes called verditer, green bice, or mountain green.

<span class="mw-page-title-main">Fehling's solution</span> Chemical test for the reducibility of a sugar

In organic chemistry, Fehling's solution is a chemical reagent used to differentiate between water-soluble carbohydrate and ketone functional groups, and as a test for reducing sugars and non-reducing sugars, supplementary to the Tollens' reagent test. The test was developed by German chemist Hermann von Fehling in 1849.

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

Copper(II) sulfate is an inorganic compound with the chemical formula CuSO4. It forms hydrates CuSO4·nH2O, where n can range from 1 to 7. The pentahydrate (n = 5), a bright blue crystal, is the most commonly encountered hydrate of copper(II) sulfate, while its anhydrous form is white. Older names for the pentahydrate include blue vitriol, bluestone, vitriol of copper, and Roman vitriol. It exothermically dissolves in water to give the aquo complex [Cu(H2O)6]2+, which has octahedral molecular geometry. The structure of the solid pentahydrate reveals a polymeric structure wherein copper is again octahedral but bound to four water ligands. The Cu(II)(H2O)4 centers are interconnected by sulfate anions to form chains.

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

Copper(II) nitrate describes any member of the family of inorganic compounds with the formula Cu(NO3)2(H2O)x. The hydrates are blue solids. Anhydrous copper nitrate forms blue-green crystals and sublimes in a vacuum at 150-200 °C. Common hydrates are the hemipentahydrate and trihydrate.

<span class="mw-page-title-main">Copper(II) oxide</span> Chemical compound – an oxide of copper with formula CuO

Copper(II) oxide or cupric oxide is an inorganic compound with the formula CuO. A black solid, it is one of the two stable oxides of copper, the other being Cu2O or copper(I) oxide (cuprous oxide). As a mineral, it is known as tenorite. It is a product of copper mining and the precursor to many other copper-containing products and chemical compounds.

<span class="mw-page-title-main">Aluminium chloride</span> Chemical compound

Aluminium chloride, also known as aluminium trichloride, is an inorganic compound with the formula AlCl3. It forms a hexahydrate with the formula [Al(H2O)6]Cl3, containing six water molecules of hydration. Both the anhydrous form and the hexahydrate are colourless crystals, but samples are often contaminated with iron(III) chloride, giving them a yellow colour.

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

Copper(II) chloride, also known as cupric chloride, is an inorganic compound with the chemical formula CuCl2. The monoclinic yellowish-brown anhydrous form slowly absorbs moisture to form the orthorhombic blue-green dihydrate CuCl2·2H2O, with two water molecules of hydration. It is industrially produced for use as a co-catalyst in the Wacker process.

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

Nickel(II) chloride (or just nickel chloride) is the chemical compound NiCl2. The anhydrous salt is yellow, but the more familiar hydrate NiCl2·6H2O is green. Nickel(II) chloride, in various forms, is the most important source of nickel for chemical synthesis. The nickel chlorides are deliquescent, absorbing moisture from the air to form a solution. Nickel salts have been shown to be carcinogenic to the lungs and nasal passages in cases of long-term inhalation exposure.

<span class="mw-page-title-main">Copper(II) hydroxide</span> Hydroxide of copper

Copper(II) hydroxide is the hydroxide of copper with the chemical formula of Cu(OH)2. It is a pale greenish blue or bluish green solid. Some forms of copper(II) hydroxide are sold as "stabilized" copper(II) hydroxide, although they likely consist of a mixture of copper(II) carbonate and hydroxide. Cupric hydroxide is a strong base, although its low solubility in water makes this hard to observe directly.

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

Copper(II) acetate, also referred to as cupric acetate, is the chemical compound with the formula Cu(OAc)2 where AcO is acetate (CH
3
CO
2
). The hydrated derivative, Cu2(OAc)4(H2O)2, which contains one molecule of water for each copper atom, is available commercially. Anhydrous copper(II) acetate is a dark green crystalline solid, whereas Cu2(OAc)4(H2O)2 is more bluish-green. Since ancient times, copper acetates of some form have been used as fungicides and green pigments. Today, copper acetates are used as reagents for the synthesis of various inorganic and organic compounds. Copper acetate, like all copper compounds, emits a blue-green glow in a flame.

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

Copper(II) fluoride is an inorganic compound with the chemical formula CuF2. The anhydrous form is a white, ionic, crystalline, hygroscopic salt with a distorted rutile-type crystal structure, similar to other fluorides of chemical formulae MF2 (where M is a metal). The dihydrate, CuF2·2H2O, is blue in colour.

In chemical nomenclature, the IUPAC nomenclature of inorganic chemistry is a systematic method of naming inorganic chemical compounds, as recommended by the International Union of Pure and Applied Chemistry (IUPAC). It is published in Nomenclature of Inorganic Chemistry. Ideally, every inorganic compound should have a name from which an unambiguous formula can be determined. There is also an IUPAC nomenclature of organic chemistry.

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

Copper(I) cyanide is an inorganic compound with the formula CuCN. This off-white solid occurs in two polymorphs; impure samples can be green due to the presence of Cu(II) impurities. The compound is useful as a catalyst, in electroplating copper, and as a reagent in the preparation of nitriles.

<span class="mw-page-title-main">Biuret test</span> Chemical test for detecting peptide bonds

In chemistry, the biuret test, also known as Piotrowski's test, is a chemical test used for detecting the presence of at least two peptide bonds in a molecule. In the presence of peptides, a copper(II) ion forms mauve-colored coordination complexes in an alkaline solution. The reaction was first observed in 1833; In Poland, the biuret test is also known as Piotrowski's test in honor of the Polish physiologist Gustaw Piotrowski who independently rediscovered it in 1857. Several variants on the test have been developed, such as the BCA test and the Modified Lowry test.

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

Iron(III) nitrate, or ferric nitrate, is the name used for a series of inorganic compounds with the formula Fe(NO3)3.(H2O)n. Most common is the nonahydrate Fe(NO3)3.(H2O)9. The hydrates are all pale colored, water-soluble paramagnetic salts.

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

Copper(I) bromide is the chemical compound with the formula CuBr. This white diamagnetic solid adopts a polymeric structure akin to that for zinc sulfide. The compound is widely used in the synthesis of organic compounds and as a lasing medium in copper bromide lasers.

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

Copper(II) phosphate are inorganic compounds with the formula Cu3(PO4)2. They can be regarded as the cupric salts of phosphoric acid. Anhydrous copper(II) phosphate and a trihydrate are blue solids.

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

Copper(II) perchlorate is an inorganic compound with the chemical formula Cu(ClO4)2(H2O)x. The anhydrous solid is rarely encountered but several hydrates are known. Most important is the perchlorate salt of the aquo complex copper(II) perchlorate hexahydrate, [Cu(H2O)6]2+.

<span class="mw-page-title-main">Copper compounds</span> Chemical compounds containing copper

Copper forms a rich variety of compounds, usually with oxidation states +1 and +2, which are often called cuprous and cupric, respectively. Copper compounds, whether organic complexes or organometallics, promote or catalyse numerous chemical and biological processes.

References

  1. 1 2 3 NIOSH Pocket Guide to Chemical Hazards. "#0150". National Institute for Occupational Safety and Health (NIOSH).
  2. "Wouter's Practical Pyrotechnics page". Archived from the original on 2007-01-07.
  3. Wells, A.F. (1984) Structural Inorganic Chemistry, Oxford: Clarendon Press. ISBN   0-19-855370-6.
  4. T. Kawata, H. Uekusa, S. Ohba, T. Furukawa, T. Tokii, Y. Muto, M. Kato "Magneto-structural correlation in dimeric copper(II) benzoates" Acta Crystallogr. 1992, vol. B48, pp. 253-261. doi : 10.1107/S0108768191012697
  5. Koizumi, Hideo; Osaki, Kenji; Watanabé, Tokunosuké (1963). "Crystal Structure of Cupric Benzoate Trihydrate Cu(C6H5COO)23H2O". Journal of the Physical Society of Japan. 18 (1): 117–124. Bibcode:1963JPSJ...18..117K. doi:10.1143/JPSJ.18.117.