At 0.9 bar of pressure and 373.15 K, the hypothetical transition from liquid to gaseous water will result in what change in the total entropy of the “universe”? No change An increase in the total entropy A decrease in the total entropy 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.

For each of the following changes, do you expect the entropy to increase or decrease? (These questions do not require calculations.) a. Ammonia gas and hydrogen chloride gas react to deposit solid ammonium chloride on a surface b. Two aqueous solutions are combined to form a precipitate c. Methanol gas condenses to form liquid methanol d. Butane liquid reacts with oxygen gas to form carbon dioxide gas and gaseous water e. Liquid water freezes to form ice f. Solid lead melts g. A solid solute dissolves in a liquid solvent h. Liquid water boils Possible answers: 1. Entropy should increase (more positive) 2. Entropy should decrease (more negative) 3. The change in entropy cannot be determined from the information given

1