Ethanol ( C₂H₅OH)melts at -114 °C.The enthalpy of fusion is 5.02 kJ mol^-1.The specific heats of solid and liquid ethanol are 0.97 J g^-1 °C^-1 and 2.3 J g^-1 °C^-1,respectively.How much heat (kJ)is needed to convert 25.0 g of solid ethanol at -145 °C to liquid ethanol at -60 °C? A)6.58 B)9.96 C)8.88 D)3859 E)-13.56

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Explanation:Heat required to raise the temperature of solid ethanol from -145 °C to -114 °C = 25 g * 0.97 J g^-1 °C^-1 * ( -114 - (-145) ) °C = 722.5 JHeat required to melt 25 g of ethanol at -114 °C = 25 g * 5.02 kJ mol^-1 * (1 mol / 46 g) = 2.72 kJHeat required to raise the temperature of liquid ethanol from -114 °C to -60 °C = 25 g * 2.3 J g^-1 °C^-1 * ( -60 - (-114) ) °C = 3.14 kJTotal heat required = 722.5 J + 2.72 kJ + 3.14 kJ = 6.58 kJ

Ethanol ( C2H5OH)melts at -114 °C

Ethanol ( C₂H₅OH)melts at -114 °C