Answer the following about LiF: a. What are the enthalpy and entropy for this reaction and over what temperature range is lithium fluoride soluble? LiF(s) --> Li+ (aq) + F-(aq) b. The observed solubility of LiF in water is 0.134 g in 100 mL of water. Is that consistent with the result in a? Explain why it is or is not.

1.  Ammonia can be made from the reaction of nitrogen and hydrogen: N2  (g)  +  3 H2 (g)      ⟺        2 NH3 (g) For this reaction, K = 1.6 x 102 and ΔH = -91.8 kcal/mole at 25oC. Is the reaction endothermic or exothermic? Briefly explain. Is there in increase in entropy, a decrease in entropy, or no change in entropy?  Briefly explain. At 25oC, is this reaction product favored or reactant favored? Briefly explain. Do you expect this reaction to be spontaneous at all temperatures?  Briefly explain.

The change in entropy, ASxn, is related to the the change in the number of moles of gas molecules, Angas. Determine the change in the moles of gas for each of the reactions and decide if the entropy increases, decreases, or has little or no change. А. 2 H, (g) + O,(g) 2 H,O(1) An gas The entropy, ASixn, mol O has little or no change. O decreases. O increases. В. H,0,(1) H, (g) + O,(g) The entropy, A.SPxn, Angas = mol O increases. O decreases. has little or no change. O O

Consider the following reaction at 25 * C : 2N2O (g) +O2(g) <—> 4 NO (g) a. At equilibrium, [N2O]=1.00M,[NO]=1.00M, and [O2 ]=0.50 M. Determine the standard Gibbs free energy at the given temperature.  b. Using information from part a determine the delta S* when Delta H* =197.7 kJ at 25 degrees * C  c. At the given temperature, will products or reactants be favored at equilibrium? Explain two reasons why

a. The molar volume of a certain solid is 142.0 cm3 mol−1 at 1.00 atm and 427.15 K, its melting temperature. The molar volume of the liquid at this temperature and pressure is 152.6 cm3 mol−1.  At 1.2 MPa the melting temperature changes to 429.26 K. Calculate the enthalpy (KJ/mol) and entropy of fusion (J/mol-K) of the solid. b. Calculate the melting point of ice under a pressure of 10 MPa. Assume that the density of ice under these conditions is approximately 0.915 g cm−3 and that of liquid water is 0.998 g cm−3. From the result of the calculation, what happens when you increase the pressure on water, will it freeze or will the ice melt?

Which of the following statements explains why CO2 sublimates instead of melts at atmospheric pressure? a. the chemical potentials of gaseous CO2and liquid CO2 become equal  b. the chemical potential of liquid CO2is greater than the chemical potential of gaseous CO2 under these conditions c. liquid CO2and gaseous CO2 have equal entropy under these conditions  d. the pressure temporarily decreases at the sublimation point

35 36 37 Which of the following should have the greatest molar entropy at 298 K? A. CH4(g) B. H₂O(1) C. NaCl(s) D. N2₂04(g) E. H₂(g) Cobalt (II) hydroxide, Co(OH)2(s), is dissolved in water forming a saturated solution having pH 9.36. Calculate Ksp for CO(OH)2. A. 4.5 × 10-¹4 B. 2.0 × 10-¹3 C. 6.0 × 10-15 D. 8.0 × 10-¹6 E. 4.0 × 10-13 What is the coefficient of I when the following redox reaction is balanced in acidic medium using smallest integers? 3+ Cr₂O72- + I→ 12+ Cr³+ A. 2 B. 3 C. 4 D. 5 E. 6

What is the entropy of vaporization?_______J/mol      What is the enthalpy of vaporization?_______kJ/mol

The enthalpy of vaporization of CH3OH is 6.40 kJ/mol. What is the entropy change for vaporization of 20.0 g CH3OH if the boiling point of it is 40.0 0C? (atomic weight in amu: C 12.00; H 1.00; O 16.00) OA. 5.0 /k O B. 12.8 J/K Oc. 20.5 J/K 18.5 J/K OD. 100 J/K OE.