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│Item │Standards │
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│Assay │Not less than 95% (v/v) │
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│Description │Colorless, odourless and flammable gas│
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│Boiling temperature │-42 ℃ │
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│Solubility │One volume of water dissolves 0.065 │
│ │volumes at 17.8 ℃ and 753 mmHg; 1 │
│ │volume of anhydrous alcohol dissolves │
│ │7.9 volumes at 16.6 ℃ and 754 mmHg; 1│
│ │volume of ether dissolves 9.26 volumes│
│ │at 16.6 ℃ and 757 mmHg; 1 volume of │
│ │chloroform dissolves 12.99 volumes at │
│ │21.6℃ and 757 mmHg. │
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│Infrared absorption │The spectrum of a sample exhibits │
│spectrum │maxima, among others, at approximately│
│ │3.4μm(vs), 6.8μm(s), and 7.2μm(m). │
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│Moisture purity │Not more than 0.005 % │
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│High-boiling residue│Not more than 5 mg/kg │
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│Acidity of │Add 10 mL of water to the sample, mix │
│high-boiling residue│by swirling for about 30 s, add 2 │
│ │drops of methyl orange TS, insert the │
│ │stopper in the tube, and shake the │
│ │tube vigorously. No pink or red color │
│ │appears in the aqueous layer. │
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│Sulfur compounds │Carefully open the container valve to │
│analysis │produce a moderate flow of gas. Do not│
│ │direct the gas stream toward the face,│
│ │but deflect apportion of the stream │
│ │toward the nose. The gas is free from │
│ │the characteristic odor of sulfur │
│ │compounds. │
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