Each data set below represents a different reaction They are not related For

# Each data set below represents a different reaction

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14. Each data set below represents a different reaction. They are not related. For which of the data sets will the corresponding reaction ALWAYS be spontaneous?a) Ho= − 45.2 KJ/mol; So= + 8.3 J/mol∙Kb) Ho= − 15.2 KJ/mol; So= 15.4 J/mol∙Kc) Ho= + 21.9 KJ/mol; So= + 70.5 J/mol∙Kd) Ho= + 30.7 KJ/mol; So= − 12.3 J/mol∙Ke) none can be chosen because the information is insufficient.Short answer. Points as shown.15. (6 pts) Draw a circle around the species in each pairbelow that has GREATERentropy. (a) MgCl2(s) vs. MgCl2(in solution) at the same temperature (b) N2(l), T = 20 K vs. N2(l), T = 50 K (c) CO2 (s) vs CO2 (g) at the same temperature (d) GaAs (s) gallium arsenide vs BN (s) (boron nitride) at the same temperature (e) C (graphite) vs. C (diamond)at the same temperature (f) CH3-CH2-CH3(g) vs CH3-CH2-CH2-CH2-CH3(g) at the same temperature Computations.SHOW WORK for partial credit. No credit awarded if no work is shown.16. (8 pts) A reaction proceeds as follows: 3 NO2(g) + H2O (l) 2 HNO3 (l) + NO (g)Calculate G for this reaction when it occurs at 450 K (non-standard temp), given the instantaneous partialpressures and concentrations shown. The Gofor this reaction is + 6.0 KJ.4
PNO2 = 0.42 atm [H2O (l)] = 55.56 M [HNO3 (l)] = 15.9 M PNO= 0.033 atm 17. POCl3decomposes according to the reaction 2 POCl3(g) 2 PCl3(g) + O2 (g)(a) (4 pts) From data in the table, calculate Gofor this reaction. (b) (1 pt) Is this reaction spontaneous at standard temperature and pressure conditions?(circle one)Yes No(c) (1 pt) Justify your choice in part (b) with a brief phrase or statement.(d) (2 pts) The value of Sofor this reaction is 179 J/K. (Note the units. This is for the reaction as written, not just one mole.) Calculate Hfo for this reaction.Compound orelementGfo,,kJ/molPOCl3(g)−502O20PCl3(g)−270.5
(e) (1 pt) In what temperature range is this reaction spontaneous? Assume H and S are constant and donot change appreciably with temperature. Justify your answer and/or show by calculation.18. (7 pts) The two solutions below are mixed together. Show by calculation if a precipitate will form. Kspfor Sr3(PO4)2= 9.68 x 10−32solution 1: 25.00 mL of 7.50 x 10−3M Sr(NO3)2solution 2: 25.00 mL of 1.50 x 10-4M K3PO46

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