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| Names | |||
|---|---|---|---|
| IUPAC name
Molybdenum trioxide
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| Other names | |||
| Identifiers | |||
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3D model (JSmol)
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| ChEBI | |||
| ChemSpider | |||
| ECHA InfoCard | 100.013.823 | ||
| EC Number |
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PubChem CID
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| UNII | |||
| UN number | 3288 | ||
CompTox Dashboard (EPA)
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| Properties | |||
| MoO3 | |||
| Molar mass | 143.95 g·mol−1 | ||
| Appearance | yellow solid | ||
| Odor | odorless | ||
| Density | 4.70 g/cm3[1] | ||
| Melting point | 802 °C (1,476 °F; 1,075 K)[1] | ||
| Boiling point | 1,155 °C (2,111 °F; 1,428 K)(sublimes)[1] | ||
| 1.066 g/L (18 °C) 4.90 g/L (28 °C) 20.55 g/L (70 °C) | |||
| Band gap | >3 eV (direct)[2] | ||
| +3.0·10−6 cm3/mol[3] | |||
| Structure[4] | |||
| Orthorhombic, oP16 | |||
| Pnma, No. 62 | |||
a = 1.402 nm, b = 0.37028 nm, c = 0.39663 nm
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Formula units (Z)
|
4 | ||
| see text | |||
| Thermochemistry[5] | |||
Heat capacity (C)
|
75.0 J K−1 mol−1 | ||
Std molar
entropy (S⦵298) |
77.7 J K−1 mol−1 | ||
Std enthalpy of
formation (ΔfH⦵298) |
−745.1 kJ/mol | ||
Gibbs free energy (ΔfG⦵)
|
-668.0 kJ/mol | ||
| Hazards[7] | |||
| GHS labelling: | |||
 
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| Warning | |||
| H319, H335, H351 | |||
| P201, P202, P261, P264, P271, P280, P281, P304+P340, P305+P351+P338, P308+P313, P312, P337+P313, P403+P233, P405, P501 | |||
| NFPA 704 (fire diamond) | |||
| Flash point | Non-flammable | ||
| Lethal dose or concentration (LD, LC): | |||
LD50 (median dose)
|
125 mg.kg (rat, oral)[citation needed] 2689 mg/kg (rat, oral)[6] | ||
LDLo (lowest published)
|
120 mg Mo/kg (rat, oral) 120 mg Mo/kg (guinea pig, oral)[6] | ||
LC50 (median concentration)
|
>5840 mg/m3 (rat, 4 hr)[6] | ||
| Related compounds | |||
Other cations
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Chromium trioxide Tungsten trioxide | ||
Related molybdenum oxides
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Molybdenum dioxide "Molybdenum blue" | ||
Related compounds
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Molybdic acid Sodium molybdate | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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-oxid_Kristallstruktur.png)
Molybdenum trioxide describes a family of inorganic compounds with the formula MoO3(H2O)n where n = 0, 1, 2. The anhydrous compound is produced on the largest scale of any molybdenum compound since it is the main intermediate produced when molybdenum ores are purified. The anhydrous oxide is a precursor to molybdenum metal, an important alloying agent. It is also an important industrial catalyst.[8] It is a yellow solid, although impure samples can appear blue or green.
Molybdenum trioxide occurs as the rare mineral molybdite.
- ^ a b c Haynes, p. 4.77
- ^ Balendhran, Sivacarendran; Walia, Sumeet; Nili, Hussein; Ou, Jian Zhen; Zhuiykov, Serge; Kaner, Richard B.; Sriram, Sharath; Bhaskaran, Madhu; Kalantar-zadeh, Kourosh (2013-08-26). "Two-Dimensional Molybdenum Trioxide and Dichalcogenides". Advanced Functional Materials. 23 (32): 3952–3970. doi:10.1002/adfm.201300125. S2CID 95301280.
- ^ Haynes, p. 4.134
- ^ Åsbrink, S.; Kihlborg, L.; Malinowski, M. (1988). "High-pressure single-crystal X-ray diffraction studies of MoO3. I. Lattice parameters up to 7.4 GPa". J. Appl. Crystallogr. 21 (6): 960–962. doi:10.1107/S0021889888008271.
- ^ Haynes, p. 5.15
- ^ a b c "Molybdenum (soluble compounds, as Mo)". Immediately Dangerous to Life or Health Concentrations (IDLH). National Institute for Occupational Safety and Health (NIOSH).
- ^ "Molybdenum trioxide". PubChem.
- ^ Roger F. Sebenik; et al. (2005). "Molybdenum and Molybdenum Compounds". Ullmann's Encyclopedia of Industrial Chemistry. Weinheim: Wiley-VCH. doi:10.1002/14356007.a16_655. ISBN 978-3527306732.