試題詳解

17. Liquid metal of mass m kg at 500 K is mixed with the same liquid metal of same mass at 1500 K. Given the specific heat of the metal is c cal/K, find the change in entropy (in cal/K) of the system. Take In 2 = 0.70, In 3 = 1.10, In 4 =1.40, In 5 = 1.61.
(A)+2.0 mc
(B) +0.6mc
(C)-1.0 mc
(D) +0.3 mc
(E) -0.21 mc