Heat of Fusion (H_f) of Ice
Obj:  Determine  H_f of Ice
Materials:  ice at 0^oC, insulated cups, balance, thermometer
Methods
1.  Fill the insulated cup with exactly 100.0 mL H₂O at approximately 35⁰C to 40^oC.  Record the mass of the cup and water and the temperature to 0.1^oC just before adding the ice cube.
2.  Add a "dry" ice cube at 0^oC to the cup; hold it submerged with another insulated cup; stir gently.
3.  Avoid spilling water.  Record the lowest temperature observed and the final mass of the system.
4.  Calculate the mass of the ice cube.

Analysis
1.  Calculate the heat of fusion (H_f) of ice using the equation:                 (c of water is 4180 J/Kg ^oC)  
                        m_w c ΔT   =  m_i H_f  +  m_i c ΔT                     where m_i is the mass of the ice cube
                        (water)          (ice)      (ice water)
2.  Determine the % error.  What are some sources of error?
3.  Define H_f.
4.  Why was it desirable to use an ice cube at 0⁰C rather than at a temperature below zero Celsius?
5.  Why did we start with water at approximately 35⁰C?

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