7738-94-5 Usage
Chemical Description
Chromic acid is a strong oxidizing agent that is used in the oxidation of organic compounds.
Description
Chromic acid, CrO3, is a powerful oxidizing agent composed of dark, purplish-red, odorless crystals that are soluble in water. It has a specific gravity of 2.7, making it heavier than water. Chromic acid is a poison and corrosive to the skin, with a TLV of 0.05 mg/m3 of air. It is a known human carcinogen and has a four-digit UN identification number of 1463. The NFPA 704 designation is health 3, flammability 0, and reactivity 1, with an "oxy" prefix indicating its oxidizing properties.
Uses
Used in Chemicals Industry:
Chromic acid is used as a chemical intermediate for the production of chromates, oxidizing agents, and catalysts.
Used in Chromium-plating Industry:
Chromic acid serves as an intermediate in the chromium-plating process.
Used in Medicine Industry:
Chromic acid is used as a caustic agent in certain medical applications.
Used in Process Engraving Industry:
Chromic acid is utilized in process engraving for etching purposes.
Used in Anodizing Industry:
Chromic acid is employed in anodizing processes to improve the surface properties of metals.
Used in Ceramic Industry:
Chromic acid is used in the production of ceramic glazes.
Used in Glass Industry:
Chromic acid is used in the manufacturing of colored glass.
Used in Metal Cleaning Industry:
Chromic acid is employed as a cleaning agent for metals.
Used in Inks Industry:
Chromic acid is used in the formulation of certain types of inks.
Used in Tanning Industry:
Chromic acid is utilized as a tanning agent in the leather industry.
Used in Paints Industry:
Chromic acid is used in the production of paints to enhance their properties.
Used in Textile Industry:
Chromic acid is used as a mordant in textile dyeing processes.
Used in Plastics Industry:
Chromic acid is employed as an etchant for plastics, improving their surface characteristics.
Air & Water Reactions
Water soluble.
Reactivity Profile
A very powerful oxidizing agent, confirmed human carcinogen. Upon contact with reducing reagents Chromic acid can cause a violent explosion, in contact with organic matter Chromic acid may cause a violent oxidation leading to ignition. Dangerously reactive with acetone, alcohols, alkali metals (sodium, potassium), ammonia, arsenic, dimethylformamide, hydrogen sulfide, phosphorus, peroxyformic acid, pyridine, selenium, sulfur, and many other chemicals [Sax, 9th ed., 1996, p. 852]. When mixed with sulfuric acid for glass cleaning operations, used solution in closed bottle may explode due to internal pressure of carbon dioxide arising from contamination by carbon compounds [Bryson, W. R., Chem. Brit., 1975, 11, p. 377].
Hazard
A human carcinogen. A poison. Corrosive
to skin. Powerful oxidizing agent, may explode on
contact with reducing agents, may ignite on contact with organic materials. Upper respiratory tract
irritant.
Health Hazard
Very irritating to eyes and respiratory tract. Ingestion causes severe gastrointestinal symptoms. Contact with eyes or skin causes burns; prolonged contact produces dermatitis (``chrome sores'').
Safety Profile
Confirmed human
carcinogen. Poison by subcutaneous route.
Mutation data reported. A powerful
oxidzer. A powerful irritant of skin, eyes,
and mucous membranes. Can cause a
dermatitis, bronchoasthma, “chrome holes,”
damage to the eyes. Dangerously reactive.
Incompatible with acetic acid, acetic
anhydride, tetrahydronaphthalene, acetone,
alcohols, alkali metals, ammonia, arsenic,
bromine penta fluoride, butyric acid, n,ndimethylformamide, hydrogen sulfide,
peroxyformic acid, phosphorus, potassium
hexacyanoferrate, pyridme, selenium
Potential Exposure
n chromium plating; medicine, ceramic glazers, and paints.
Shipping
UN1463 Chromium trioxide, anhydrous, Hazard Class: 5.1; Labels: 5.1-Oxidizer, 6.1-Poisonous materials, 8-Corrosive material. UN1755 (solution) Chromic acid, solid, Hazard class: 8; Labels: 8-Corrosive material.
Incompatibilities
A strong oxidizer. Aqueous solution is strongly acidic. Reacts with acetic acid, acetic anhydride, acetone, anthracene, chromous sulfide; diethyl ether; dimethyl formamide; ethanol, hydrogen sulfide; methanol, naphthalene, camphor, glycerol, potassium ferricyanide, pyridine, turpentine, combustibles; organics, and other easily oxidized materials (such as paper, wood, sulfur, aluminum, and plastics). Attacks metals in presence of moisture
Waste Disposal
Chemical reduction to chromium(III) can be followed by land fill disposal of the sludge.
Check Digit Verification of cas no
The CAS Registry Mumber 7738-94-5 includes 7 digits separated into 3 groups by hyphens. The first part of the number,starting from the left, has 4 digits, 7,7,3 and 8 respectively; the second part has 2 digits, 9 and 4 respectively.
Calculate Digit Verification of CAS Registry Number 7738-94:
(6*7)+(5*7)+(4*3)+(3*8)+(2*9)+(1*4)=135
135 % 10 = 5
So 7738-94-5 is a valid CAS Registry Number.
InChI:InChI=1/Cr.2H2O.2O/h;2*1H2;;/q+2;;;;/p-2/rCrH2O4/c2-1(3,4)5/h2-3H
7738-94-5Relevant articles and documents
UV-vis spectroscopic determination of the dissociation constant of bichromate from 160 to 400°C
Chlistunoff, Jerzy B.,Johnston, Keith P.
, p. 3993 - 4003 (1998)
On the basis of direct measurements by UV-vis spectroscopy, the dissociation constant of bichromate was found to decrease with temperature from 160 to 400°C. For fixed Cr(VI) and KOH concentrations, the molal concentration of HCrO4- initially increases with temperature but decreases again in the vicinity of water's critical point, where the density decreases substantially. The decrease in HCrO4- at high temperature and low density may be attributed to (K+)(CrO42-) ion pairs, to a high degree of electrostriction about CrO42-, which facilitates the reaction HCrO4- + OH- = CrO42- + H2O, and to ion activity coefficients.
Theoretical and experimental investigation of the thermochemistry of CrO2(OH)2(g)
Opila, Elizabeth J.,Myers, Dwight L.,Jacobson, Nathan S.,Nielsen, Ida M. B.,Johnson, Dereck F.,Olminsky, Jami K.,Allendor, Mark D.
, p. 1971 - 1980 (2007)
In this paper, we report the results of equilibrium pressure measurements designed to identify the volatile species in the Cr-O-H system and to resolve some of the discrepancies in existing experimental data. In addition, ab initio calculations were performed to lend confidence to a theoretical approach for predicting the thermochemistry of chromium-containing compounds. Equilibrium pressure data for CrO2(OH)2 were measured by the transpiration technique for the reaction 0.5Cr2O3(s) + 0.75O2(g) + H2O(g) = CrO2(OH)2(g) over a temperature range of 573 to 1173 K at 1 bar total pressure. Inductively coupled plasma atomic emission spectroscopy (ICP-AES) was used to analyze the condensate in order to quantify the concentration of Cr-containing volatile species. The resulting experimentally measured thermodynamic functions are compared to those computed using B3LYP density functional theory and the coupled-cluster singles and doubles method with a perturbative correction for connected triple substitutions [CCSD(T)].
Vaporisation of chromia in humid air
Gindorf,Singheiser,Hilpert
, p. 384 - 387 (2005)
Thermodynamic data for the computation of the vaporisation of Cr 2O3(s) in humid air show significant deviations between each other which lead to large differences in the computed partial pressures. The vaporisation of Cr2O3(s) in air with different humidities, p(H2O)=0.0007 bar to p(H2O)=0.3 bar, was, therefore, investigated at constant temperature of 1223 K by the vapour transpiration method. The results obtained were explained by the formation of CrO3(g) as major vapour species at low p(H2O) and the formation of CrO2(OH)2(g) as major vapour species at high p(H2O). The pressures evaluated are compared with those obtained by thermodynamic computations using different data bases.
Gemcitabine derivatives nanoparticles
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Page/Page column 4, (2009/05/28)
The invention concerns a 2′,2′-difluoro-2′-deoxycytidine derivative of general formula (I), wherein: R1, R2 and R3, identical or different, represent independently of one another, a hydrogen atom or an at least C18 hydrocarbon acyl radical and of such conformation that it is capable of providing the compound of general formula (I), a compacted form in a polar solvent medium, at least one of groups R1, R2 and R3 being other than a hydrogen atom.
PYRROLIDINE DERIVATIVES AS OXYTOCIN ANTAGONISTS
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Page 30-31, (2008/06/13)
The present invention relates to novel pyrrolidine derivative of formula (I), its geometrical isomers, its optically active forms as enantiomers, diastereomers, mixtures of these and its racemate forms, as well as salts thereof, wherein R1 is selected from the group comprising or consisting of H and C1-C6-alkyl, for the prevention and/or treatment of preterm labor, premature birth or dysmenorrhea.