Heat of Fusion & Heat of Vaporization

Part 1: Heat of FusionPart 2: Heat of Vaporization

Virtual Lab: Melting Ice

0.00 g

Electronic balance

--.- °C

Laboratory bench

1. Mass Empty Cup2. Add ~75 mL Water3. Mass Cup + Water4. Measure Initial T5. Add Ice & Mix6. Remove Unmelted Ice7. Final MassReset / New Trial

Begin by measuring the empty foam cup.

Procedure Progress

1. Mass the foam cup.
2. Add approximately 75.0 mL of warm water.
3. Mass the cup and warm water.
4. Measure the initial water temperature.
5. Add 3–4 ice cubes and mix until within 1°C of 0°C.
6. Remove any unmelted ice.
7. Mass the cup, water, and melted ice.

Heat of Fusion Data

Measurement	Value	Unit
Mass of foam cup		g
Mass of cup + warm water		g
Mass of warm water		g
Initial temperature		°C
Final mixture temperature		°C
Final mass: cup + water + melted ice		g

Record each displayed measurement. Calculate the mass of warm water by subtraction.

Virtual Lab: Vaporizing Water

0.0 min

≈ ≈

5.0 mL sample

≈

100.0 mL sample

--.- °C

1. Add Water2. Turn On Hot Plates3. Record T When 5 mL Boils4. Record T When VaporizedReset / New Trial

Add 5.0 mL and 100.0 mL of water to the two beakers.

Procedure Progress

1. Add 5.0 mL to the small beaker and 100.0 mL to the large beaker.
2. Place both on identical hot plates and begin heating.
3. Record the large sample temperature when the small sample begins boiling.
4. Record the large sample temperature when the small sample has completely vaporized.

Heat of Vaporization Data

Measurement	Value	Unit
Temperature of 100.0 mL sample when 5.0 mL begins boiling		°C
Temperature of 100.0 mL sample when 5.0 mL is completely vaporized		°C

The energy gained by the 100.0 g sample during this interval estimates the energy used to vaporize the 5.0 g sample.