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b) Assume that Hokium acts as an ideal gas. It is a(Circle one): monoatomic linear or nonlinearΔHovapHokium = kJ/molShow your work to support your answer to b.c) What is the change in entropy for last two steps shown on the graph (vaporization of 1 mole of Hokium@ 250K and heating of the resulting gas to 300 K)?ΔS = J/K59810002100022662.82002252502753003250500010000150002000025000Temperature(K)heat added (J)Hea1ng curve for Hokium
CHEM_230_W16_PREP_E1p 46) The graph below shows 0.2 moles of a linear gas taking two different pathways for expanding from point A (5 atm, 0.1L, 298K) to point C (1.5 atm, 0.25L, 223.5K) The first path contains two steps: step 1 (Z1) is a reversible isothermal expansion from A to B followed by step 2 (Z2), cooling from B to C. The second path (X) is an adiabatic expansion from A to C.11.522.533.544.550.050.10.150.20.250.3Pressure(atm)Volume (L)A (5 atm, 0.1 L, 298K)B (2atm, 0.25 L, 298K)C (1.5 atm, 0.25L, 223.5K)step Z1step Z2path Xa) What are the values for the following quantities for each step of each path? Use units of J. Show work for any calculations. Indicate the appropriate sign.Step Z1UwqJJJStep Z2UwqJJJPath XUwqJJJ18b) An adiabatic expansion leads to less work done on the surroundings than an isothermal expansion.Circle one:True False2
CHEM_230_W16_PREP_E1p 57) 0.0818 mol of copper requires 3612 J to heat it from 298K to 1500K. Copper melts at 1358 K; copper has a ΔHofus= 13.1 kJ/mol; copper solid has a molar heat capacity of 24.43 J/(K mol). What is the molar heat capacity of liquid copper?10Cm, liquid Cu= J/(K mol)13) One mole of an ideal gas is studied at a constant temperature. The volume of the gas at different pressures is measured. Given the plot and equation shown below, at what temperature was the data collected?P (pressure, atm)1/V (1/volume, 1/L)y = [20.93 (L atm)] (x)T = K8
CHEM_230_W16_PREP_E1p 6866410) Assume ideal gases. A manometer is used to monitor the decomposition of N2O5(g). To set up the experiment, one side of the mercury manometer is placed under vacuum. The other side of the manometer is connected to a 10.0 L rigid reaction flask, filled with N2O5,and then heated to 70.0oC.2 N2O5 (g)--> O2(g)+ 4 NO2(g)ONONO2isa) The height difference of the mercury in the manometer at 70oC is 256.7 mm. How many moles of N2O5are in the flask before decomposition? (Assume no change in density of Hg with temperature.)b) The N2O5decomposes completely as shown in the balanced chemical equation. Assuming constant temperature what is the new height difference in the mercury in the manometer?mol N2O5(g)=height difference: mmc) What is the partial pressure of oxygen after the decomposition reaction?PO2: atmd) The decomposition products are cooled from 70oC to 25oC. What are the q and w for this process?q = Jw = J(include signs)
CHEM_230_W16_PREP_E1p 74611) Air is approximately 80% by volume nitrogen and approximately 20% by volume oxygen. An experiment to study air was set up as shown in the figure in the box below. The rigid 200 mL flask on the left is filled with oxygen at STP (0oC, 1 atm). The rigid 800 mL flask on the right is filled with nitrogen at STP (0oC, 1 atm). The two flasks are joined by a closed stopcock. Assume ideal gases.