Additional Problems, Chapter 3

1.      Calculate the difference in molar entropy between liquid water and ice at –5 ^oC.  The molar heat capacities at constant pressure, of liquid water and ice are 75.31 and 37.7 J K^-1 mol^-1, respectively, and the molar enthalpy of fusion of water at 0.00 ^oC is 6.01 kJ mol^-1. Ans. –21.3 J K^-1mol^-1.

2.    A 355 mL can filled with a soft drink, initially at 25 ^oC, is placed in an ice-chest filled with an equilibrium mixture of ice and water at 1 atm pressure.  (a) What is the final temperature of the can and its contents once it reaches thermal equilibrium with the ice-water mixture?  (b) What is the entropy change of the can and the soft drink?  The mass of the empty aluminum can is 14.37 g,  and the heat capacity of aluminum is 24.35 J K^-1 mol^{- 1}. Take the heat capacity of the drink to be the same as that of water, that is,   = 75.31 J K^-1 mol^-1.  (c) What is the entropy change of the ice-water mixture?  (d) What is the total entropy change for the drink, the can and the ice-water mixture inside the cooler? Ans. (b) –131.1 J/K, (c) +137.0 J/K.

3.    Calculate the standard molar entropy of "your" compound, either ammonia, benzene or sulfur dioxide,  using MC.  Sample MC.