A tank is divided into two equal chambers by an internal diaphragm. One chamber contains methane at a pressure of 500 bar and a temperature of 20°C, and the other chamber is evacuated. Suddenly, the diaphragm bursts. Compute the final temperature and pressure of the gas in the tank after sufficient time has passed for equilibrium to be attained. Assume that there is no heat transfer between the tank and the gas and that methane: 

a. Is an ideal gas; 

b. Obeys the principle of corresponding states of Sec. 6.6; 

c. Obeys the van der Waals equation of state; 

d. Obeys the Peng-Robinson equation of state; Data: For simplicity you may assume C^∗_P = 35.56 J/(mol K).