QI/ A gas in a piston-cylinder assembly undergoes an expansion process for which the relationship between pressure and volume is given by pVn=constant. The initial pressure is 3 bar, the initial volume is 0.1 m3, and the final volume is 0.2 m3. Determine Solution and discussion: 1. 1. The expansion is a. Fast b. graduated c. fully damped d. adiabatic. 2. 2. The energy means: a. Em – Eout = 0 b. H1 = H2 c. Q12 AU12 d. AĖ12 # 0 %3D %3D in

2. a. Take B °C, then convert it to Fahrenheit and Kelvin. b. Find the amount of heat needed to change the temperature of B g of ice from -D °C to B °C. The specific heat of water is 4186 J/kg °C, Latent heat of fusion is 3.33 x105 J/kg, laten heat of vaporization 2.25 x 106 J/ kg. c. A patient of mass B kg is spiking a fever of 105 Fahrenheit. The patient is immersed in ice bath 0°C ice to reduce the fever immediately back down to 98.6 Fahrenheit. How much ice must melt (bath stays at 0°C water) for this temperature reduction to be achieved? Latent heat of fusion is 3.33 x105 J/kg. and Specific heat of body is 3500 J/kg °C. d. A Styrofoam ice box has a total area of C/100 m² and walls with an average thickness of 2.50 cm. The box contains beverages at 0°C. The inside of the box is kept cold by melting ice. How much ice melts in one day if the ice box is kept in the trunk of a car at 35.0°C? Thermal conductivity of ice 0.010 J/s m ºC, Latent heat of fusion is 3.33 x105 J / kg. B:27.0…

2. An ideal gas (the weight is m kg) in an idealized piston-cylinder assembly undergoes a series of processes from state 1 to states 2, 3 and 4. Each state is at equilibrium. The gas can be modeled as a closed system. Ignore changes of KE and PE. The states are fixed by the following properties in the table: State 1 2 3 4 8 7 9 Note: State 1 to 2 is a constant-temperature process. State 2-3 is a constant-volume process. State 3-4 is a constant-temperature process. (a) Mark the states 1-4 and draw the three processes (1-2, 2-3, 3-4) on the following p-v diagram. p (bar) 4 5 3 1 2 0 p (bar) 1 3 1 6 3 v (m³/kg) 3 1 1 2 2 300K 600K T (K) 300 300 600 600 3 4 5 v (m³/kg) 6 7 8 (b) Use equations and simple texts to explain and answer the questions for the two processes (process 1-2, and process 2-3), respectively. (i) How does the internal energy change during each process: no change, increase or decrease (AU)? (ii) How does the enthalpy change during each process (AH)? (iii) Is the work…