TEACHER
CAUTION: Before performing this activity, be sure
that no student who will enter the room or be exposed to the
smoke has a peanut allergy.
PART
1 QUESTIONS
QUESTIONS

What was the volume of water that was heated by the burning
peanut? (accept all reasonable answers)
 What
was the initial temperature of the water? What was the
final temperature of the water? How many °C did it rise?
(this value is obtained by subtracting the initial water
temperature from the final water temperature)
 Use
the following equation to determine the heat gained by
the water:
Calories = (mass of water) (change in temperature of water)
For our approximation, we'll equate mLs and grams, therefore:
calories = (volume of water) (change in temperature of
water)
We'll also simplify our calculations by assuming that
minimal heat was lost to the surroundings. Therefore,
we'll set the heat gained by the water equal to the heat
lost by the peanut.
 What
was the initial mass of the peanut? What was the final
mass of the peanut? What was the mass of the peanut that
was burned? (the mass of the peanut burned is obtained
by subtracting the final mass of the peanut from its initial
mass)
 To
calculate the calories per gram of the peanut, use the
following equation:
calories per gram = (heat gained by water)/(mass lost
when peanut burned)

To calculate the number of nutritional Calories per gram
simply divide the heat calories from question 5 by 1000.
EXTENSIONS
WATER'S
MASS
To
simplify our calculations, we set the mass of 1 mL equal to
1 gram. How accurate is such an approximation? To find out,
use a laboratory balance to obtain the mass of a beaker. Record
this value. Use a graduated cylinder to introduce 100 mL of
water to this beaker. Determine its new mass. Subtract the
initial mass from the final mass to obtain the mass of 100
mL of water. Divide this value by 100 to obtain the mass of
1 mL. Was the approximation you used in the previous experiment
acceptable? Explain. (accept all reasonable answers)
LOSING
HEAT
The
experimental design was flawed. All of the energy released
by the burning peanut was not absorbed by the water. Where
did it go? (changed into light, absorbed by the test tube
glass, lost as heat to the surrounding air) Can you design
a better setup in which less heat energy is lost? Think about
it. Then create a set of blueprints for a laboratory tool
that would more efficiently transfer heat from a burning material
to a quantity of water.
CURRICULUM
LINKS
Chemistry:

Chemical
Reactions, Heat of Reaction 
Biology:

Health,
Nutrition 

NATIONAL
SCIENCE STANDARDS (Grades
58)
Science
As InquiryContent Standard A 
Students
should develop abilities necessary to do scientific inquiry, 
Students should develop an understanding about scientific
inquiry 
Physical
Science Content Standard B 
Students should develop and understanding of the
properties and changes of properties in matter 
Students should develop and understanding transformations
of energy 
Science
and Personal and Social Perspectives Content Standard
F 
Student
should develop an understanding about personal health 
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