In the Dumas Method for determining the molar mass of an unknown liquid with a boiling...

In the Dumas Method for determining the molar mass of an unknown liquid with a boiling point less than water, the liquid is vaporized in a bulb (whose volume is precisely known) that is immerse in a water bath. The bulb is sealed after all the liquid has been evaporated. The bulb is cooled and the gas that has filled the container condenses. The bulb is weighed and the weight of the liquid in the bulb is determined by weighing the bulb before the experiment and after the experiment. The following data for an unknown liquid is obtained using the Dumas Method:

Measurement	Value
Volume of the Bulb	351 mL
Mass of the Bulb before the Experiments	2.000 g
Mass of the Bulb after the Experiment	2.506 g
Pressure	722 torr
Temperature	80 oC

The gas in the Dumas bulb must be

CH3SH

CH3CH2CH2OH

CH3CH2OCH2CH3

CH3CH2OH

CH3COOH

Solutions

Expert Solution

queen_honey_blossom answered 1 year ago

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