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Appearance
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Colourless, cubic crystals or white crystalline powder
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Identification
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-
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Sodium (Na)
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Meets the requirement
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Chloride (Cl)
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The precipitate dissolves easily with the possible exception of a few large particles, which dissolve more slowly
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Assay (on dried basis)
|
99.0 – 100.5%
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Aluminium (Al)
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NMT 0.2 ppm
|
|
Arsenic (As)
|
NMT 1 ppm
|
|
Barium (Ba)
|
Any opalescence in the test solution is not more intense than that in the reference solution
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|
Ferrocyanide [(Fe(CN)6]4-
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No blue color develops in 10 min
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Iodides
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No blue color is observed
|
|
Iron (Fe)
|
NMT 2 ppm
|
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Bromides
|
NMT 100 ppm
|
|
Phosphatase
|
NMT 25 ppm
|
|
Potassium (K)
|
NMT 500 ppm
|
|
Magnesium and alkali earth metals
|
NMT 100 ppm
|
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Nitrites
|
NMT 0.01%
|
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Sulphate (SO4)
|
NMT 200 ppm
|
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Appearance of solution
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This solution is clear and colourless
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Acidity or alkalinity
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NMT 0.5 mL of 0.01N hydrochloric acid or 0.01N sodium hydroxide is required to change the color of this solution
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Loss on drying
|
NMT 0.5%
|