Experiment 3 Determination of Molar Mass by Vapor Density

Experiment 3 Determination of Molar Mass by Vapor Density 

Background The Ideal Gas Law can be used to determine the approximate molecular mass 

When there was no more liquid visible in the flask, the student then placed the flask into cold water so that the vapor could condense. She dried the flask thoroughly and then reweighed the flask and determined the mass of the condensed vapor to be 0.430 g. The student then checked the barometric pressure of the room and found it to be 750. torr. 

Calculate the molecular mass of the unknown. What possible sources of error were not accounted for in the calculations  

Explain how the following errors would affect the calculated molecular mass  

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