ldt s the change in its entropy? Given b = 0.06 dm' mol, Cym29.0 J K no Two dm' of methane under 4 bar and 298 K and 4 dm? of oxygen under 20 bar and 298 K are 1orced 36. to a 5 dm evacuated reaction vessel, the temperature being maintained at 298 KCacua change n entropy of gases assuming that they are ideal. 37. A thermally insulated vessel is divided into two compartments by a partition of insulating material.