Aluminium Hydroxide Paste
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SL. NO
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TESTS
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STANDARDS
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1
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Characters
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A
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Description |
A white, pasty material; small amounts of clear liquid
may separate on standing. |
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B
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Solubility |
Insoluble in water and in ethanol (95%). It dissolves
in dilute mineral acids and in excess of caustic alkali solutions. |
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2
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Identification
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A
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Reaction of Aluminium salts | |||
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i
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Reaction A
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Gelatinous white precipitate should re-appear.
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ii
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Reaction B
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An intense purple colour should be formed.
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iii
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Reaction C
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A reddish violet colour should be formed.
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3
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pH
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Between 8.5 and 10.0
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4
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Arsenic
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Not more than 1ppm. | ||
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5
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Heavy Metals
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Not more than 10 ppm
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6
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Chloride
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Not more than 0.25%
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7
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Sulphate
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Not more than 0.3%
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8
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Neutralising Capacity
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Not more than 50 ml of 0.1M sodium hydroxide should
be required. |
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9
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Microbial contamination
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Total viable aerobic count, not more than 100 micro-organisms
per ml. 1 g should be free from Escherichia coli. |
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|
10
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Assay
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Between 8.0% and 10.0% (of Al2O3)
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