Calculate the mass of a gas that need to be released from a system to reach a specific pressure

300.2 g of oxygen gas at 34.0 ˚C are contained within a 27.1 L cylinder under atmospheric pressure.  Determine the mass of the oxygen gas th...

300.2 g of oxygen gas at 34.0 ˚C are contained within a 27.1 L cylinder under atmospheric pressure.  Determine the mass of the oxygen gas that must be released in order for the pressure to be 1.11 atm, in the cylinder.