2. (a) (b) (c) (d) (e) The van der Waals equation of state can be used to estimate any one of the state variables, P, T, and , if the other two variable values are specified for a particular gas. Discuss. [20%] Methane (CH4) is stored at 200 bar and 15C in a 12.4 m vessel. What is the state of the methane in the vessel under these conditions? (10%] Using the ideal gas equation estimate the mass of methane contained in the vessel under the conditions specified in (b)? [20%] Using the Van der Waals equation of state estimate the mass of methane contained in the vessel for those conditions specified in (b). [40%] The storage vessel is fitted with a pressure relief valve which is set to vent the methane at a pressure of 300 bar. Using the van der Waals equation estimate the temperature to which the cylinder may be raised before the methane is released. [10%] The van der Waals equation of state is, RT 27R?T? RTC p= where and b= - b 2 For Methane Critical Temperature, T. =-82.45C Critical Pressure, Pc = 46.4 bar a a= 64pc 8pc Note: 1 bar = 1.0x105 N/m2 and R= 8.3145 J/mol K