Chromium trioxide

Chromium trioxide
Ball-and-stick model of chromium trioxide
  Chromium, Cr
  Oxygen, O
Powder of chromium trioxide
Names
IUPAC name
Chromium trioxide
Other names
Chromic anhydride, Chromium(VI) oxide, Chromic acid (misnomer)
Identifiers
3D model (JSmol)
ChEBI
ChemSpider
ECHA InfoCard 100.014.189 Edit this at Wikidata
RTECS number
  • GB6650000
UNII
UN number 1463
  • InChI=1S/Cr.3O checkY
    Key: WGLPBDUCMAPZCE-UHFFFAOYSA-N checkY
  • InChI=1/Cr.3O/rCrO3/c2-1(3)4
    Key: WGLPBDUCMAPZCE-YFSAMUSXAF
  • O=[Cr](=O)=O
Properties
CrO3
Molar mass 99.993 g·mol−1
Appearance Dark red granular solid, deliquescent
Odor Odorless
Density 2.7 g/cm3 (20 °C)[1]
Melting point 197 °C (387 °F; 470 K)[1]
Boiling point 250 °C (482 °F; 523 K)
decomposes[1]
  • 164.8 g/(100 mL) (0 °C)
  • 169 g/(100 mL) (25 °C)[1]
  • 172.6 g/(100 mL) (40 °C)
  • 198.1 g/(100 mL) (100 °C)[2]
Solubility Soluble in H2SO4, HNO3, (CH3CH2)2O, CH3COOH, (CH3)2CO
+40·10−6 cm3/mol[1]
Thermochemistry
73.2 J/(mol·K)[3]
−589.3 kJ/mol[4]
Hazards
GHS labelling:
GHS03: OxidizingGHS05: CorrosiveGHS06: ToxicGHS08: Health hazardGHS09: Environmental hazard[5]
Danger
H271, H301+H311, H314, H317, H330, H334, H335, H340, H350, H361f, H372, H410[5]
P210, P260, P280, P303+P361+P353, P304+P340+P310, P305+P351+P338[5]
NFPA 704 (fire diamond)
[6]
NFPA 704 four-colored diamondHealth 4: Very short exposure could cause death or major residual injury. E.g. VX gasFlammability 0: Will not burn. E.g. waterInstability 2: Undergoes violent chemical change at elevated temperatures and pressures, reacts violently with water, or may form explosive mixtures with water. E.g. white phosphorusSpecial hazard OX: Oxidizer. E.g. potassium perchlorate
4
0
2
OX
Lethal dose or concentration (LD, LC):
80 mg/kg (rats, oral)[6]
Safety data sheet (SDS) ICSC 1194
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
checkY verify (what is checkY☒N ?)

Chromium trioxide (also known as chromium(VI) oxide or chromic anhydride) is an inorganic compound with the formula CrO3. It is the acidic anhydride of chromic acid, and is sometimes marketed under the same name.[6] This compound is a dark-purple solid under anhydrous conditions and bright orange when wet. The substance dissolves in water accompanied by hydrolysis.[clarification needed] Millions of kilograms are produced annually, mainly for electroplating.[7] Chromium trioxide is a powerful oxidiser, a mutagen, and a carcinogen.[8]

  1. ^ a b c d e Lide, David R., ed. (2009). CRC Handbook of Chemistry and Physics (90th ed.). Boca Raton, Florida: CRC Press. ISBN 978-1-4200-9084-0.
  2. ^ Seidell, Atherton; Linke, William F. (1919). Solubilities of Inorganic and Organic Compounds (2nd ed.). D. Van Nostrand Company. p. 250.
  3. ^ "chromium(VI) oxide". chemister.ru.
  4. ^ Pradyot, Patnaik (2003). Handbook of Inorganic Chemicals. The McGraw-Hill Companies, Inc. ISBN 0-07-049439-8.
  5. ^ a b c Sigma-Aldrich Co., Chromium(VI) oxide. Retrieved on 2021-11-22.
  6. ^ a b c "Chromium trioxide". chemicalland21.com. AroKor Holdings Inc. Retrieved 2014-06-15.
  7. ^ Anger, G.; Halstenberg, J.; Hochgeschwender, K.; Scherhag, C.; Korallus, U.; Knopf, H.; Schmidt, P.; Ohlinger, M. (2000). "Chromium Compounds". Ullmann's Encyclopedia of Industrial Chemistry. doi:10.1002/14356007.a07_067. ISBN 3527306730.
  8. ^ Mamyrbaev, Arstan Abdramanovich; Dzharkenov, Timur Agataevich; Imangazina, Zina Amangalievna; Satybaldieva, Umit Abulkhairovna (2015-04-16). "Mutagenic and carcinogenic actions of chromium and its compounds". Environmental Health and Preventive Medicine. 20 (3). Springer Science and Business Media LLC: 159–167. doi:10.1007/s12199-015-0458-2. ISSN 1342-078X. PMC 4434237. PMID 25877777.