Mass of dry flask, foil, rubber band (g) = 74.722

Temp of boiling water (C,K) = 98.7,371.7

Mass of dry flask, foil, rubber band, vapor = 74.921

Volume of flask = 0.152 L

Atmospheric pressure (torr, atm) = 752, 0.98947

moles of vapor = 4.9*10^-3 mol

molar mass = 40.6 g/mol

If the atmospheric pressure of the flask is assumed to be 760 torr in the question, what is the reported molar mass of the vapor?

What is the percent error caused by the error in the recording of the pressure of the vapor?