Two Experimental Runs Are Performed to Determine the Calorimetric Properties

Multiple Choice

Two experimental runs are performed to determine the calorimetric properties of an alcohol which has a melting point of -10.0° C.In the first run,a 200-g cube of frozen alcohol,at the melting point,is added to 300 g of water at 20.0°C in a styrofoam container.When thermal equilibrium is reached,the alcohol-water solution is at a temperature of 5.0°C.In the second run,an identical cube of alcohol is added to 500 g of water at 20.0°C and the temperature at thermal equilibrium is 10.0°C.The specific heat capacity of water is 4190 J/kg ∙ K.Assume no heat is exchanged with the styrofoam container and the surroundings.What is the heat of fusion of the alcohol?

A) 5.5 × 10⁴ J/kg
B) 6.3 × 10⁴ J/kg
C) 7.1 × 10⁴ J/kg
D) 7.9 × 10⁴ J/kg
E) 8.7 × 10⁴ J/kg