MHS Chemistry
Heat of Fusion Practice
A student is trying to find the heat of fusion for ethanol. The specific heat of liquid ethanol is 2.1 J/gC, and its freezing point is –114.4 C.
The student used 100.0 grams of liquid ethanol at –100.0 C, and 20.0 grams of frozen ethanol at –114.4 C. The final temperature of the mixture is –110.0 C.
Show all of your work for each of the following questions, and use the proper number of significant digits in each answer.
1. What is the melting point for ethanol?
2. What is the change in temperature of the liquid ethanol?
3. What is the change in energy of the liquid ethanol?
4. What is the change in energy of the just-melted ethanol that warms up?
5. What is the heat of fusion, in J/g, for ethanol?
6. If the “accepted” value for the heat of fusion of ethanol is
104.1 J/g, what is the percent error for this student’s trial?