Thermodynamic 2 Test (1) Time=1:30

Question One:

1) true or false question:a. when going through phase change both temperature and

pressure are constantb. Single phase regions are all temperature independentc. Two phase regions are all pressure and temperature

independent

2) Use Gibbs relation du = Tds – Pdv and one of Maxwell’s relations to find an expression for (∂u/∂P)T that only has properties P, v and T involved. What is the value of that partial derivative if you have an ideal gas?

3) Estimate the change in enthalpy and entropy when liquid ammonia at 270K is compressed from its saturation pressure of 381Kpa to 1200Kpa. For saturated liquid ammonia at 270K, Vt= 1.551 x10-3m3 kg-1and β = 2.095 x 10-3K-1.

4) A mixture of 2 kmol of CO and 3 kmol of O2 is heated to 2600 K at a pressure of 304 kPa. Determine the equilibrium composition, assuming the mixture consists of CO2, CO, and O2.

Note: ln KP = 2.801, or KP = 16.461

Question Two:

1. Talk briefly about Retrograde Condensation?2. Assuming Raoult's law to be valid, prepare a P-x-y diagram for a

temperature of 363.15 K (90°C) and a t-x-y diagram for a pressure of 90 kPa for Benzene(l)/ethylbenzene(2).