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Appearance
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A pale yellow, green or gray powder
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Assay
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Min 99.5%
|
|
Substance insoluble in dilute NH3 (C=8.3%)
|
Max 0.01%
|
|
Chloride (Cl)
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Max 0.002%
|
|
Arsenate, phosphate, silicate ( PO4)
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Max 0.001%
|
|
Sulphate (SO4)
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Max 0.02%
|
|
Ammonium (NH4)
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Max 0.002%
|
|
Nitrate (NO3)
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Passes ACS test (~0.003%)
|
|
Phosphate (PO4)
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Max 0.0005%
|
|
Heavy metal (as Pb)
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Max 0.005%
|