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Trial 1 - Temperature of Mixing Water

1. Obtain 1 small Styrofoam cup and 1 large one. Fill the small cup part way with cold water (ice water with no ice cubes). Put a little bit of the warm water in the large cup.

   

2. Connect the temperature sensor to the computer. Refer to Technical Hints to connect the temperature sensor. Put the temperature sensor in the small cup. Measure the temperature. When recording the temperature, wait until the temperature read by the sensor stops decreasing, then record your result. Refer to Technical Hints to record a single measurement.

   

   Cold Water Temperature:

   
   
3. Repeat the process for the large cup of water, and record your results below.

   Warm Water Temperature:

   
   
4. Make a prediction. What do you think the temperature will be when you mix the two cups of water?

   Predicted Final Temperature:

   
   
5. How did you come up with this prediction?
   
   
6. Pour the small cup of water into the large cup. Measure and record the temperature below.

   

   Actual Final Temperature:

   
   
7. Is the temperature close to what you expected? Explain.
   
   
8. Now you are going to mix two more samples of water. Pour your water out and add some hot water to the large cup. Instead of ice water, add cool water from a faucet or jug to the small cup. Using the temperature sensor, measure the initial water temperatures in each cup, and then make a prediction for a final temperature. Record your measurements and predictions in the Mixture 1 line of the table below.

   	Small Cup Initial Temp (degrees C)	Large Cup Initial Temp (degrees C)	Mixture Predicted Final Temp (degrees C)	Mixture Actual Final Temp (degrees C)
   Mixture 1
   Mixture 2
   Mixture 3
   Mixture 4

   
   
9. When you mix the water from both cups, measure the final temperature and record your results in the table below.

   	Small Cup Initial Temp (degrees C)	Large Cup Initial Temp (degrees C)	Mixture Predicted Final Temp (degrees C)	Mixture Actual Final Temp (degrees C)
   Mixture 1
   Mixture 2
   Mixture 3
   Mixture 4

   
   
10. Try a few more mixtures. Repeat the process in steps 8 and 9 a few times with cups of varying temperatures of water and fill in the table under Mixture 2, 3, and 4.

    	Small Cup Initial Temp (degrees C)	Large Cup Initial Temp (degrees C)	Mixture Predicted Final Temp (degrees C)	Mixture Actual Final Temp (degrees C)
    Mixture 1
    Mixture 2
    Mixture 3
    Mixture 4

    
    
11. Look at the table with your team members. Compare the final temperatures with the initial temperatures. Do you see a pattern? Explain.
    
    
12. Sometimes it is easier to understand data while looking at a table and other times looking at a graph can be helpful. Try drawing a bar chart on the grid below with the Small Cup, Large Cup and Actual Final Mixture Temperatures from the table.
    
    
13. What seems to be true about the final water temperature in all the cases you recorded?