| | Identification | More |  | [Name] 
 Molybdic acid
 |  | [CAS] 
 7782-91-4
 |  | [Synonyms] 
 AMMONIUM DIMOLYBDATE
 AMMONIUM MOLYBDATE
 AMMONIUM MOLYBDATE (DI)
 AMMONIUM MOLYBDATE REAGENT
 AMMONIUM MOLYBDATE TS
 AMMONIUM MOLYBDENUM OXIDE (DI)
 diammonium dimolybdate
 MOLYBDIC ACID
 (beta-4)-molybdate(moo42-dihydrogen
 dihydrogen,(T-4)-Molybdate
 MOLYBDIC ACID, A.C.S. REAGENT
 MOLYBDIC ACID CA. 85 % MOO3 (COMMER-CIAL QUALITY, CONTAINS AMMONIUM
 MOLYBDIC ACID  >=85.0% AS MOO3   A.C.S&
 MolybdicAcid85%ExtraPure
 MolybdicAcid>98%
 MolybdicAcidAr
 MolybdicAcid85%Gr
 MolybdicAcidReagent
 Molybdic acid, pract.
 Molybdicacid,ACS,MoO385%min
 |  | [EINECS(EC#)] 
 231-970-5
 |  | [Molecular Formula] 
 H2MoO4
 |  | [MDL Number] 
 MFCD00010882
 |  | [Molecular Weight] 
 161.95
 |  | [MOL File] 
 7782-91-4.mol
 | 
 | Chemical Properties | Back Directory |  | [Definition] 
 Molybdic acid of commerce iseither ammonium molybdate (molybdic acid 85%)or molybdenum trioxide. The use of the term inter-changeably for these compounds has caused con-fusion. Solutions of molybdic acid are very com-plex chemically since they show a great tendencyto polymerize.
 |  | [Appearance] 
 white to slightly yellow powder
 |  | [Melting point ] 
 300 °C
 |  | [bulk density] 
 980kg/m3
 |  | [density ] 
 3.1 g/mL at  25 °C(lit.)
 |  | [vapor density ] 
 6.2 (vs air)
 |  | [storage temp. ] 
 Store at +5°C to +30°C.
 |  | [solubility ] 
 slightly soluble in H2O; soluble in alkaline solutions
 |  | [form ] 
 white powder
 |  | [color ] 
 White powder
 |  | [Specific Gravity] 
 3.1
 |  | [Odor] 
 Odorless
 |  | [PH] 
 3.46(1 mM solution);2.94(10 mM solution);2.43(100 mM solution)
 |  | [Water Solubility ] 
 70 g/l (20 ºC)
 |  | [Merck ] 
 13,6263
 |  | [Exposure limits] 
 ACGIH: TWA 0.5 mg/m3
 NIOSH: IDLH 1000 mg/m3
 |  | [CAS DataBase Reference] 
 7782-91-4(CAS DataBase Reference)
 |  | [EPA Substance Registry System] 
 7782-91-4(EPA Substance)
 | 
 | Safety Data | Back Directory |  | [Hazard Codes ] 
 Xi
 |  | [Risk Statements ] 
 R36/37/38:Irritating to eyes, respiratory system and skin .
 |  | [Safety Statements ] 
 S24/25:Avoid contact with skin and eyes .
 S22:Do not breathe dust .
 |  | [WGK Germany ] 
 3
 |  | [TSCA ] 
 Yes
 |  | [HS Code ] 
 28111990
 | 
 | Questions And Answer | Back Directory |  | [Descriptioin] 
 The monohydrate is a yellow solid consisting of monoclinic crystals; density 3.124 g/cm3 at 15°C; loses water of crystallization on heating at 70°C;
 sparingly soluble in cold water (1.33 g/L at 18°C); moderately soluble in hot water 25.68 g/L at 70°C; soluble in caustic soda and sodium carbonate solution. The anhydrous acid consists of white hexagonal crystals; density 3.112 g/cm3; converts to molybdenum trioxide, MoO3 at 70°C; slightly soluble in water; soluble in alkalies and sulfuric acid.
 The monohydrate is prepared by treating a molybdate solution with nitric acid, followed by crystallization which may take several weeks to separate out as a yellow solid. The anhydrous molybdic acid is obtained as a white crystalline substance by careful dehydration of the yellow monohydrate.
 | 
 | Hazard Information | Back Directory |  | [Chemical Properties] 
 white crystals or crystalline powder
 |  | [Uses] 
 Determination of phosphates.
 |  | [reaction suitability] 
 reagent type: catalyst
 core: molybdenum
 | 
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