A 2.00-kg block of ice at 0.00C is dropped into a very large lake at 25.0C and completely melts. For water, the heat of fusion is 3.35 105 J/kg,
the heat of vaporization is 2.25 105 J/kg, and the specific heat is 4190 J/kgK. The net change in entropy of the system consisting of the ice and the lake due to this melting process is closest to
A) 2.45 103 J/K.
B) 2.24 103 J/K.
C) 2.06 102 J/K.
D) -2.45 103 J/K.
E) -2.06 102 J/K.
Question 2
A brass rod, 75.0 cm long and having a cross-sectional area of 2.50 cm2, conducts heat from a large furnace at 375C into a very large cold water bath at 10.0C
without losing any heat at the lateral surface of the rod. Steady state has been established, and the thermal conductivity of brass is 109 W/mK. The rate at which the entropy of the system (furnace plus water) is changing is closest to
A) 2.05 10-2 W/K.
B) 2.64 10-2 W/K.
C) 3.54 10-2 W/K.
D) 4.69 10-2 W/K.
E) 6.74 10-2 W/K.