Ok, here is what is given: 1.00 mol O2 Ti = 300K Vi = 5.00L 4400 j of energy transfered by heat to the system Vf = ? Constant Pressure = 29.4 J/mol * K So I set the problem up using Q = n(Constant Pressure)(Tf - T-i) Solving for Tf I find that Tf is equal to 449.7K. Then using equation (Vf - Vi) = (nR(Tf - Ti)) / P Vf = ((1.00mol * 8.31 J/mol*K * 149.7K) / (1.013*10^5 N/m^2)) + 5.00L I am getting Vf = 17.28 L Can anyone tell me what I am doing wrong? My teacher told me the answer should be 7.52, could he of possibly meant 17.52? Any help would be appreciated!