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Appearance
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White powder
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Assay (alkalimetric; on dried basis)
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99.5-100.5%
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Identification
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To comply IP, BP, USP tests
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Solubility
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Soluble in water and in ethanol (96 per cent), freely soluble in boiling water and in glycerol (85 per cent)
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Appearance of solution
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To comply IP, BP, USP
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Substance insoluble in alcohol
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To comply IP, BP, USP test
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pH (3.3% solution in water)
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3.8 - 4.8
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Sulphate (SO4)
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Max 0.045%
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Heavy metal (as Pb)
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max 0.0015%
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Arsenic (As)
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Max 0.001%
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Organic impurities
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To comply BP test
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Loss on drying (5hrs; over silica gel)
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Max 0.5%
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