Consider a sample containing 5.00 mol of a monatomic ideal gas that is taken fro
ID: 744634 • Letter: C
Question
Consider a sample containing 5.00 mol of a monatomic ideal gas that is taken from state A to state B by the following two pathways: Pathway one: PA = 3.00 atm, VA = 15.0 L PC = 3.00 atm, VC = 55.0 L PB = 6.00 atm, VB = 20.0 L Pathway two: PA = 3.00 atm, VA = 15.0 L PD = 6.00 atm, VD = 15.0 L PB = 6.00 atm, VB = 20.0 L For each step, assume that the external pressure is constant and equals the final pressure of the gas for that step. Calculate q, w, E, and H for each step, and calculate overall values for each pathway. Explain how the overall values for the two pathways illustrate that E and H are state functions, whereas q and w are path functions. ** It clearly states to treat each step as constant pressure, which doesn't make any sense to begin with, but if only applied to the change from C -> B, the pressure used for q should be 6.00 atm, but nothing I try gives the correct answer.Explanation / Answer
For q find the change in temperature first using (delta)T= P(delta)V/nR (delta)T=292.46 Then, because it is at constant pressure, q=(delta)H = n*C(p)*(delta)T Where n=5, C(p)=5/2R which is 5/2*8.3145, and (delta)T=292.46 That will give you the answer for path 1 step 1 q and (delta)H. To find w, take -P*(delta)V*101.3. 101.3 is the conversion factor for Joules per L*atm. Because the gas is expanding, and therefore performing work, the energy involved is negative, the gas loses joules. For (delta)E, just add the q and w together.