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Molecular formula: Na2SO3
Molecular weight: 126.04
CAS NO: 7757-83-7
Properties: white powder with sulfur dioxide odor. It is gradually oxidized to sodium sulfate in the air. Soluble in water and slightly soluble in ethyl alcohol. Relative density is 2.663.
Uses: as analytical reagent, reducing agent, preservative and developing agent. It can be used in pharmaceutical industry.
Standard: maximum assay of impurities is in %
| Specification/item |
Analytically pure-AR
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Chemically pure-CP
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High pure
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Assay(Na2SO3)
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≥97.0
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≥95.0
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≥96.0
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Clarity test
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Qualified
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Qualified
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Water insoluble matter
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≤0.005
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≤0.01
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≤0.03
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Acid sulphite (Na2SO3)
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Qualified
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Qualified
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Free alkali (Na2CO3)
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≤0.1
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≤0.3
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≤0.5
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Chloride (Cl)
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≤0.005
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≤0.02
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≤0.05
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Thiosulfate (S2O3)
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≤0.01
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≤0.02
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≤0.04
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Iron (Fe)
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≤0.0005
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≤0.002
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≤0.003
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Heavy metal (Pb)
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≤0.001
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≤0.002
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≤0.003
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Arsenic (As)
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≤0.0001
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≤0.0005
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≤0.001
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Packing: woven bag lined with plastic bag, kraft paper bag, or fiber drum, net weight is 25kg.
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