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The latent heat of fusion of alcohol is 25 kcal/kg and its melting point is -114 o C. It has a specific heat of 0.60 in its liquid state. Calculate the energy needed to melt 2.0 kg of solid alcohol at -114 o C and raise it to a temperature of -14 o C.

User Feklee
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2 Answers

7 votes

Answer:

170 kcal

Step-by-step explanation:

User Tarod
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3 votes

Answer:

=170kcal

Step-by-step explanation:

We first calculate the amount of energy required to melt the alcohol using the formula: MLf, where Lf is the latent heat of fussion

We then calculate amount of heat required to raise the temperature of liquid alcohol to -14° C using MC∅. We then add the two.

Thus ΔH=MLf+MC∅

ΔH=2kg×25kcal/kg+ 2kg×(0.6kcal/kg.K×(-14-⁻114)

=50kcal+120kcal

=170kcal

User Ryan Shillington
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