1. The problem statement, all variables and given/known data Two kilograms of air at 5 bar, 350 K, and 5 kg of carbon monoxide, initially at 4 bar, 450 K, are confined to opposite sides of a rigid, well-insulated container by a partition. The partition is free to move and allows conduction from one gas to the other without energy storage in the partition itself. The air and carbon monoxide each behave as ideal gases with constant specific heat ratio, k = 1.395. Determine the equilibrium temperature. 2. Relevant equations Q - W = delta U Cp - Cv = R Cp/Cv = k Rair = 8.314 / Mwtair Rco = 8.314 / Mwtco Q = mCv(T2-T1) 3. The attempt at a solution Carbon Monoxide Cp - Cv = 0.297 Cp / Cv = k Cv(k) - Cv = 0.297 1.395Cv - Cv = 0.297 0.395Cv = 0.297 Cv = 0.75 Air Cp - Cv = 0.287 Cp / Cv = k 1.395Cv - Cv = 0.287 Cv = 0.73 This is where i feel i am going wrong. Q = mCv(T2-T1) Q = 0 as insulated closed system Carbon Monoxide Air 0 = 4 x 0.75 (T2 - 450) 0 = 2 x 0.73 (T2 - 350) 0 = 3T2 - 1350 0 = 1.46T2 - 511 I made the two equations equal each other (not sure if that is correct) 1.46T2 - 511 = 3T2 - 1350 839 = 1.54T2 T2 = 544.8 K I know this is the wrong answer but I am not sure why.