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Molecular formula: Na2WO4·2H2O
Molecular weight: 329.87
Properties: Colorless crystal or white crystalline powder. Weathering in the dry air. It loses water of crystallization if heated to 100℃. Relative density is 3.245. Melting point is 692℃ (anhydride). Soluble in water and insoluble in alcohol.
Uses: As analytical reagent, alkaloid precipitant, water-proofing and fire-proofing agent for fabrics. It can be used in preparing metal tungsen and other tungsen compounds.
Standard: The maximum content of impurities is in percentage content
| Standard/item |
Analytical pure-AR
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Chemical pure-CP
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Assay[Na2WO4·2H2O] /%
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≥99.5
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≥99.0
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Water insoluble matter/%
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≤0.01
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≤0.02
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Alkalinity
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Qualified
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Qualified
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Chloride(Cl) /%
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≤0.005
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≤0.007
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Sulfate(SO4) /%
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≤0.01
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≤0.02
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Nitrogen compound (N) /%
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≤0.001
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≤0.004
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Arsenic (As)/%
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≤0.0005
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≤0.0005
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Iron (Fe)/%
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≤0.0005
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≤0.001
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Heavy metal(Pb) /%
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≤0.0005
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≤0.002
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Molybdenum (Mo)
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≤0.001
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≤0.005
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Packing: Woven bag, kraft bag or fiber drum lined with plastic, net weight is 25kg.
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