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Appearance
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A white or almost white, free-flowing, granular powder
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Solubility
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Practically insoluble in water. It dissolves in dilute mineral acids with slight effervescence
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Identifications
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-
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Identification 'A'
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Solution gives reaction characteristic of aluminium salt
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Identification 'B'
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Solution gives reaction characteristic of magnesium salt
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Alkalinity
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8.0 to 10.0 (pH of 4 % w/v suspension)
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Neutralising capacity
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NLT 260 ml of 0.1 M HCI per gm
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Arsenic
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NMT 3 ppm
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Sodium
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NMT 0.1 %w/w
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Chlorides
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NMT 0.3%w/w
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Sulphates
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NMT 0.7%w/w
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Loss on ignition
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40.0% to 50.0% w/w
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Assay (as Al2O3)
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15.3% to 18.7% w/w
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Assay (as MgO)
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36.0% to 44.0% w/w
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Ratio Al2O3: MgO
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0.40 to 0.45
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