What is the Identity of the Unknown Liquid Used in a Dumas Bulb Experiment?

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SUMMARY

The discussion centers on identifying an unknown clear liquid with a calculated molar mass of 38.1 g/mol, derived from a Dumas bulb experiment. The participant's trials yielded results of 36.72, 39.56, and 49.11 g/mol, with a significant confidence interval of ±18.1 g/mol due to an error in the third trial. The liquid is characterized as safe to inhale in vapor form, lacking a distinct smell, and having a boiling point below 100 degrees Celsius. The participant is considering whether the liquid is ethanol or methanol, noting that methanol is known to be poisonous in vapor form.

PREREQUISITES
  • Understanding of Dumas bulb experiments
  • Knowledge of molar mass calculations
  • Familiarity with the properties of ethanol and methanol
  • Basic laboratory safety protocols for handling chemicals
NEXT STEPS
  • Research the properties and safety profiles of ethanol and methanol
  • Learn about Dumas bulb methodology and its applications in laboratory settings
  • Investigate methods for accurately determining molar mass in laboratory experiments
  • Explore the implications of vapor toxicity for common solvents
USEFUL FOR

This discussion is beneficial for chemistry students, laboratory technicians, and anyone involved in chemical identification and safety assessments in experimental settings.

yellowcakepie
I performed a laboratory experiment using a Dumas bulb to find the molar mass of an unknown, clear liquid in order to identify it. The Dumas bulb was submerged in a beaker filled with water (with the tip out of the water) and the water was boiled to evaporate the sample.

I eventually got a result with 38.1 g/mol as the mean, with a huge confidence interval (at 95%) of +- 18.1 g/mol. This is because I screwed up my 3rd trial so I could only use my first 2. I got results of 36.72, 39.56, and 49.11 g/mol.

I need help identifying this liquid.

The liquid is clear, safe to inhale in vapor form (I'm still alive), does not have a distinct smell, has a boiling point lower than 100 degrees C, and is not "an exotic compound".

Edit: I'm now deciding between ethanol and methanol. I'm hearing that methanol is poisonous in vapor form, so I think it may be ethanol.
 
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This appears to be lab homework, so moving the thread to homework section. No template.
 
yellowcakepie said:
does not have a distinct smell

I'm now deciding between ethanol and methanol. I'm hearing that methanol is poisonous in vapor form, so I think it may be ethanol.

These alcohols do have a quite characteristic smell.
 
Methanol isn’t really any more poisonous than other common solvents. Of course, like most common solvents, if you drink it, that’s bad news, but simply smelling it is very unlikely to hurt you.
 

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