A sample of an unknown liquid is vaporized in a 255-mL flask in a hot water bath at 100.00 Celsius....

Question

...... The atmospheric pressure is 748 torr and the vapor is found to have a mass of 0.714 grams of the vapor?

Answer 1

find the molar mass....

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first find moles using:

PV=vRT

(748Torr)(0.225Litres) = n (62.36Torr-Litres/mol-K)(373K)

n= 0.007235 moles

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now since molar mass is g/mole:

0.714 grams / 0.007235 moles = 98.68 g/mole

you answer is: Molar mass is 98.7g/mol