How Does Energy Move Between Liquids That are at Different Temperatures? By: Kristin and Kirsten

Purpose: How does energy move between liquids that are at different temperatures? Hypothesis: As hot and cold water mix, the new temperature will be between the hot and cold temperatures. Independent Variable: Amount of water (mL) Levels: 10mL20mL30mL (control)40mL50mL 2 trials Dependant Variable: Temperature of the mixed water, (°C) Constants: Amount of hot water, Temperature of the hot water, Equipment.

Procedures: 1.Measure temperature of ice water. 2.Pour 10mL of ice water into the graduated cylinder. 3.Measure 30mL of hot water. 4.Wait until the water heats up to 85°C. 5.Pour ice water into the hot water. 6.Record temperature. 7.Repeat steps 1-6 for 20, 30, 40, and 50mL of ice water.

Data Table: Trial 1- Amount of ice water (mL) Temp. of ice water (°C) Temp. of hot water (°C) Temp. of mixed water (°C)

Data Table: Trial 2- Amount of ice water (mL) Temp. of ice water (°C) Temp. of hot water (°C) Temp. of mixed water (°C)

Results Graph:

Conclusion: According to our data, the more cold water that was added to the same amount of hot water the temperature of the mixed water was colder. When we put in 50mL of cold water the temperature of the mixed water was colder. We used 85°C hot water and the temperature of the cold water was a little different each time we did it. The cold temperature was between 6°C to 11°C. We started with 10mL of cold water with 30mL of hot water and the temperature of the mixed water was 72.2°C. When we used 50mL of cold water and 30mL of hot water the mixed temperature was 42.3°C. Our hypothesis was that as more cold water was added to the hot water the mixed temperature would be between the hot and cold temperature. Our hypothesis was supported because the temperature of the mixed water was in between the hot and cold water. When we added more cold water the temperature of the mix water was closer to the temperature of the cold water.