Procedure
1. Using the method of mixtures from a standard Physics or Chemistry lab manual or the Web sites listed below, determine the specific heat and heat of fusion of water. Write all definitions and equations in the accompanying Student Data Table. If using calorimeters, follow the instructions at http://www.iit.edu/~smart/martcar/lesson5/id37.
2. Compare the specific heat values with several other liquids, us, ing the table found on the Web at http://www.engineeringtoolbox.com/specific-heat-fluids-24_151.html.
Common Liquid Specific Heat
a. _____________ _____________
b. _____________ _____________
c. _____________ _____________
3. Discuss the relevancy of these numbers and their relationship to those of others liquids to the suitability of water as a medium for living systems.
References on calorimeters and specific heat
http://hyperphysics.phy-astr.gsu.edu/hbase/thermo/calor.html
http://www.engineeringtoolbox.com/specific-heat-fluids-24_151.html
http://www.engineeringtoolbox.com/heat-work-energy-36_292.html
Part 3. Capillary action
Height of liquid in tube/straw (mm)
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Diameter of tube/straw (mm)
| 1. Define capillary action.
2. Using the deionized water, the capillary tubes or straws of different sizes, and the metric ruler, determine the height to which pure water will rise in the tubes. Record and graph your data on the graph at right, using height (mm) x inside diameter (mm).
3. Repeat the experiment with another set of tubes and a diluted soap solution. How do the graphs compare? Explain the differences in terms of surface tension, adhesion, cohesion, and the impact that soap has on these properties. (See the following Web site about Water Properties: http://www.uni.edu/~iowawet/H2OProperties.html#states.
4. Explain the relevancy of water’s capillarity to its suitability as a medium for living systems.
Part 4. Heating and cooling rates
Temperature (C)
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Time (min.)
| 1. Place equal masses of sand and water in two identical beakers.
2. Insert identical thermometers into the materials.
3. Expose the beakers either to a heat source (e.g., radiator vent, hot water bath, heat plate, sunny window sill) or to a cooling source (e.g., air conditioner vent, cold or ice water bath).
4. Observe and record the temperature of each every 5 minutes.
5. Graph and compare the rates of heating, using the graph at right.
6. Relate these results to the subnivean (“situated under the snow”) conditions that make life in cold environments more tolerable.
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