2) (25 pts) For the following processes, deduce whether each of the quantities Q. W, AT, AP, AH, and AS are positive (+), negative (-), or zero (0). The system is the substance mentioned in the problem. For 1-time processes, the system is the substance mentioned in the problem and AT, AH, and AS are between the initial and final states. For steady-state processes, the system is where the changes of state take place (for Q and W) and AT, AH, and AS are between the upstream and downstream fluids. In other words, this is exactly what we have been doing all year. a) Melting a fraction of ice into water at 1 MPa (1-time process). b) A hydrocarbon mixture of 80% octane and 20% methane (mole fractions) going through a choke valve from P = 30 MPa to P=1 MPa. You can assume that the valve operates adiabatically, and that the Joule Thompson coefficient of the mixture is greater than zero (steady-state process). c) Isobaric and isothermal mixing of 5 moles of He and 3 moles of Ne from an initial T-300K and P=0.1MPa. Please assume they form an ideal mixture. (1-time process). d) Reversible adiabatic compression of a natural gas stream (98% methane 2% ethane mole fractions) from P = 1 MPa to P-3 MPa (steady-state process). Q W AT AS ST a) b) c) d)