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Appearance
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Orange red brown or maroon powder
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Assay (on anhydrous basis)
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Min 95%
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Solubility (in 1N NaOH)
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50 mg/ml
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|
Molar absorptivity E(490+/-2nm)
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Min 70000
|
|
Molar absorptivity E(284+/-2nm)
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Min 12000
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|
Molar absorptivity E(238+/-2nm)
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Min 39000
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Loss on drying (at 105°C)
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Max 5.0%
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Melting point
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About 315 °C
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