INGOMAR MIDDLE SCHOOL SCIENCE     NAME: ______________________                    www.scied.net
Evaporation / Volatility  Lab                                 Period: ______ Date: __________ Score_____/ 20

Evaporation, the process by which liquid water is converted into a gaseous state, is a critical part of Earth's water cycle. Water vapor enters Earth's atmosphere via evaporation from puddles, ponds, streams, rivers, lakes and oceans. The water vapor is then returned to the Earth's surface as precipitation.

The rate of evaporation increases with a rise in air and water temperatures. The evaporation rate also increases with an increase in wind and solar radiation since warmer air can hold more moisture.

Hypothesize: How quickly will mass measurements change as evaporation occurs?

Data Collection & Recording:

  1. Pour water into the shallow dish or Petri dish so that the bottom of the dish is just covered.
  2. Place the dish on the balance pan.
  3. Click the Start () button on the stop watch to begin recording data with the time.
  4. Allow evaporation to proceed for a chosen length of time -- perhaps a class period.
  5. Click the Stop () button on the stop watch to end data collection.
  6. Repeat the procedure outlined above, testing other factors that may affect the rate of evaporation.

DAY/Period:
Start Time:

Weight of __________

Weight of _________

Start
Temperature

Start
Temperature

IR Temperature

Change

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10.

 

 

 

 

 

 

 

 

 

 

 

Data Analysis: Graph the results (Weight/ Time).
Weight in Grams:

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

 

Time in ______

 

Conclusion and Questions

  1. How might the rate of evaporation be different if warmer or cooler water was used, or if the atmospheric temperature were different?
  2. Try shining a bright light on the pan of water, or begin with warmer or cooler water.

     
  3. What effect does covering the dish or partially covering it have on the evaporation rate? Repeat the experiment and test your predictions.
  4. Simulate the effect of pollution on natural bodies of water by adding a few drops of detergent or oil to the surface of the water: does the rate of evaporation change?
  5. Test the evaporation rate of other samples such as salt water or compare the evaporation rate of water to other liquids such as rubbing alcohol, acetone, vinegar, etc.