A 810-g quantity of ethanol, in the liquid state at its melting point of is frozen at atmospheric pressure
The heat of fusion of ethanol is 1.04 × 105 J/kg, the molecular mass is 46.1 g/mol, and the ideal gas constant is R = 8.314 J/(mol ? K). The change in the entropy of the ethanol as it freezes is closest to
A) -540 J/K.
B) -490 J/K.
C) -600 J/K.
D) 490 J/K.
E) 540 J/K.
Answer: A
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