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Appearance
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Colorless hygroscopic solids or white crystalline powder
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Assay
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Min 99%
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Clarity of solution (1 g in 25 mL ethanol)
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Passes test
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pH (5% solution in water)
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2.5 - 3.5
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Sulphur compounds (as SO4)
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Max 0.005%
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|
Heavy metals (by ICP-OES)
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Max 0.0005%
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|
Iron (Fe)
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Max 0.0005%
|
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Ammonium (NH4)
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Passes ACS test
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Residue on ignition
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Max 0.05%
|
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Titrable free acid
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Max 0.25 meq/g
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