4. A 1.00 mole sample of a monatomic ideal gas, originally at a pressure of 1.00 atm, undergoes a three-step process: (1) it is expanded adiabatically from T1 = 550 K to T2 = 389 K, (2) it is compressed at constant pressure until its temperature reaches T3, (3) it then returns to the original pressure and temperature by a constant volume process. A. Plot these processes on a P-V diagram. B. Determine T3. C. Calculate the change in internal energy, the work done by the gas, and the heat added to the gas for each process, and for the complete cycle.

Q3: In a closed vessel with a volume of 50 dm3 there are 2 moles of an ideal monoatomic gas with cv, m = 12.471 J K-1 mol-1 at 25°C. The vessel was heated to 125°C. Calculate the values of Q, W, AU, AH in Joules and the initial and final pressure in the system. R = 8,314 J K-1 mol-1. Cp,m = 20,785 J K-1 mol-1

V. W. Th To %3D Room temperature T = 293 K V V. Vp The gas volume changes from Vp to Va at constant temperature T. The cartoon on the right shows a piston of gas undergoing this compression while submerged in a container of room temperature water, which acts as a reservoir. The initial state of this process is a piston containing 2 moles of a monatomic gas at Tc = 293 K (room temperature water) and volume V = a 1.0 m. The gas is compressed until V, = 0.2 m. During the compression, the heat bath of room temperature water maintains the temperature of the gas at T 293 K. Calculate the work done in joules by the gas during this process. Do not include units in your answer. Be careful to use the standard sign convention for work done by the gas. Write your numerical answer in normal form as described above in the instructions to this worksheet.

An amount of an ideal gas undergoes the process shown in the diagram below. Assume that during the entire cycle, the number of moles of the ideal gas stays constant. Р. A В V (a) What are the signs of Way the gast Q, and AEint for the process CA? positive positive Wby the gas AEint zero (b) What are the signs of Wby the gas Q, and AEint for the process AB? negative negative zero W by the gas AEint (c) What are the signs of Wby the gas: Q, and AEint for the process BC? Wby the gas positive Q negative DE int zero

A cylinder contains oxygen at a pressure of 2.00 atm. The volume is 4.00 L, and the temperature is 300 K. Assume that the oxygen may be treated as an ideal gas. The oxygen is carried through the following processes: (i) Heated at constant pressure from the initial state (state 1) to state 2, which has T = 450 K. (ii) Cooled at constant volume to 250 K (state 3). (iii) Compressed at constant temperature to a volume of 4.00 L (state 4). (iv) Heated at constant volume to 300 K, which takes the system back to state 1. (a) Show these four processes in a pV-diagram, giving the numerical values of p and V in each of the four states. (b) Calculate Q and W for each of the four processes. (c) Calculate the net work done by the oxygen in the complete cycle. (d) What is the efficiency of this device as a heat engine? How does this compare to the efficiency of a Carnot-cycle engine operating between the same minimum and maximum temperatures of 250 K and 450 K?

WA 4. a Th To Room temperature T = 293 K %3D V The gas volume changes from Vp to Va at constant temperature T. The cartoon on the right shows a piston of gas undergoing this compression while submerged in a container of room temperature water, which acts as a reservoir. The initial state of this process is a piston containing 2 moles of a monatomic gas at T, = 293 K (room temperature water) and volume V = 1.0 m. The gas is compressed until V, = 0.2 m. During the compression, the heat bath of room temperature water maintains the temperature of the gas at T = 293 K. Calculate the change in internal energy of the gas in joules during this process. Do not include units in your answer. Be careful to use the standard sign conventions for heat and work. Write your numerical answer in normal form as described above in the instructions to this worksheet. Click Save and Submit to save and submit. Click Save All Answers to save all answers. 28 F a

● Determine the missing properties and the phase descriptions in the following table for water: T, °C 125 75 P, KPa 200 1000 500 800 u, kJ/kg 1600 2950 X 0.6 0.0 Phase Description

A PV diagram below, Figure 1, shows two possible states of a system containing three moles of a monatomic ideal gas. (P,= P2 = 450 Pa, V, = 2m', V,= 8m²) c. Draw the process which depicts an isothermal expansion from state 1 to the volume V, followed by an isochoric increase in temperature to state 2 and label this process (B). d. Find the change in internal energy of the gas for the two-step process (B) Figure 1 (N/m²) 500 ! 400+ 300+ 200+ 100 - + + + + 4 6. 8 10 V (m³) 2 Copyright © 2005 Pearson Prentice Hall, Inc.

Consider the processes shown below for a monatomic ideal gas.   Find the work done in each of the processes AB, BC, AD, and DC. Hint for (a)   WAB=WAB=CorrectJJWBC=WBC=IncorrectJJWAD=WAD=IncorrectJJWDC=WDC=CorrectJJ Find the change in the internal energy in processes AB and BC. Hint for (b)   ΔEAB=ΔEAB=IncorrectJJΔEBC=ΔEBC=IncorrectJJ Find the total heat added in ABC and ADC processes. Hint for (c)   QABC=QABC=IncorrectJJQADC=QADC=IncorrectJ

Please answer A and D.