Corban E. answered 12/16/19
AP Chemistry Tutor and Former Teacher (Gen Chem, IB, O-Level, A-Level)
Initially, it's at 80 C. The boiling point is 76.72 C, so it is a gas.
Use the volume of the sample and the density of the gas to determine the mass.
This problem does not give the density of the gas, so the mass of the gas cannot be determined from the mL given, so the problem has not given enough information to provide the answer.