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Appearance
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Silky white crystals or crystalline powder; odourless; sublimes readily
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Assay (on dried basis)
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99.0- 101.5%
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Solubility
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Sparingly soluble in water, freely soluble in boiling water, slightly soluble in ethanol (96 per cent). It dissolves in concentrated solutions of alkali benzoates or salicylates.
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Identification
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To comply IP,BP test
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Appearance of solution
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To comply IP,BP test
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Melting point
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235 - 237°C
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Insoluble matter in water
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Max 0.005%
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Acidity or alkalinity
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To comply IP/BP test
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Related Substances
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To comply IP,BP test
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Sulphate (SO4)
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Max 0.05%
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Heavy metal (as Pb)
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Max 0.002%
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Loss on drying ((at 105°C for 1hr)
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Max 0.5%
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Sulphated ash
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Max 0.1%
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Copper (Cu)
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Max.0.0002%
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Iron (Fe)
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Max.0.0002%
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Lead (Pb)
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Max.0.0002%
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Zinc (Zn)
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Max.0.0002%
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Theobromine (C7H8N4O2)
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Max.0.2%
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