Calorimetry

Albert Oldenburg               Lindblom Tech. H.S.
                               6130 So. Wolcott
                               Chicago, Il. 60636
                               312-535-9300

Objective:

     To develop an understanding of the fundamentals of calorimetry.  That the 
students will learn how to manipulate and set up the equipment and the 
development of increasing and decreasing amounts of heat.

Materials:

    Three gallon plastic pail, 12 oz. plastic or styrofoam cups, calorimeters 
with aluminum inside cups, metal dial thermometers, triple beam or double pan 
balances, set of masses, about three gallons of water, hot plates, ice cubes, 
and a pencil and paper.

Strategy:

This lesson is usually used as the first in the series of heat experiments.  A 
brief demonstration comparing a large amount of heated water versus a small 
amount at the same temperature shows the large difference in calories.  This 
should show how to capture heat with water.  The 'hook' for the lesson was "If a
person were weight conscious, would it be better to drink ice tea or hot tea?"  
From here the instructor has the class weigh the styrofoam cup, about 200 grams 
of water and two ice cubes.  They would stir them with a metal dial thermometer 
until the cubes are melted, taking note and recording the temperature.  The 
groups would then calculate the calories from the mass and temperature 
difference.  A small discussion follows to see that everybody is following.  The
next part is to determine the calories in a cup of hot water.  The styrofoam cup
need not be weighed but the room temperature water and the hot water are.  The 
mixture is stirred and the highest temperature is recorded.  From this the 
calories are determined for the 'hot tea'.  A discussion of the calories from 
the hot tea compared to the iced tea concludes that it would be better to drink 
the iced tea if a person were calorie conscious.  This should help students to
better understand how to scientifically determine a calorie and how to set up an
experiment to do it.