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Appearance
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A white to very pale yellow crystalline powder or colourless crystals; odourless. On exposure to light it gradually darkens.
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Assay
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99.5-100.5%
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Identity (IR)
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To confirm the structure
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Identification (as per USP, IP)
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To comply the tests
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Appearance of solution
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To comply IP test
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Specific optical rotation ([α]20/D; 10% solution)
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+20.5° to +21.5°
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Light absorption
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Absorbance at about 244 nm is about 0.56
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Oxalic acid
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Max 0.3%
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Loss on drying
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Max 0.1%
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Sulphated ash
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Max 0.1%
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Chloride (Cl)
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Max 0.01%
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Sulphate (SO4)
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Max 0.002%
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Copper (Cu)
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Max 0.0005%
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Heavy metal (as Pb)
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Max 0.001%
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Iron (Fe)
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Max 0.0002%
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Lead (Pb)
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Max 0.001%
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