[tooworried]

For those unfamiliar: In the Dumas method, we find the molar mass of an unknown volatile liquid by placing a pure sample into an Erlenmeyer flask, and sealing it with aluminum foil and a rubber band. A small hole is poked into the foil. The flask is placed into a hot water bath and the liquid is vaporized.

My question: When cooling the flask to room temp, some vapor condenses inside the flask. Will the calculated molar mass be unaffected?