A gaseous compound is placed in a rigid container of volume 10.0 L at temperature 300.0 K and at pressure 1.0 atm. The container is placed in an evacuated chamber and a small hole of area 2.65 mm2 is made in one of the container walls. It takes 1.00 minutes for the gas pressure in the container to fall to half of its original value. Determine the molar mass of the gas.