Physical Science Institute
Summer 2013
Degrees of Separation
Teacher Guide
Note: This guide only contains sample data for the first trial in part 2
MATERIALS per 3 person group
LabQuest2
Beaker
Styrofoam cups
100 ml graduated cylinder
1 Temperature Probe
Hot Plate
Vendor
Fisher
Fisher
VERNIER
VERNIER
Fisher
Fisher
Description
Scale, top-Loading
Graduated Cylinder
LabQuest2
Temperature Probe
250 mL beaker
Hot Plate
Item Number
S94792K
S31857
LBQ2
TMP-BTA
S30730-6
11-100-16H
SAMPLE DATA
Data Table 1
Part One
Mass
Initial Temperature
Final Temperature
Cold Water
40 g
23.6 °C
31.9 °C
Warm Water
40 g
40.2 °C
31.9 °C
Data table 2
Part 2
Mass of
Warm
Water
Initial
Temperature
(Warm water)
Mass of
Cold
Water
1
60 grams
39.9°C
2
80 grams
20 grams
3
60 grams
12 grams
30 grams
Initial
Temperature
(Cold Water)
26.6 °C
Final
Temperature
35.3°C
Decrease in
Temperature
(Warm water)
4.6°C
Increase in
Temperature
(Cold Water)
8.7°C
Physical Science Institute
Summer 2013
CALCULATIONS & RESULTS
Calculate the increase and decrease in temperatures and record in Data Table 2.
PART 1:
1. What was the temperature increase of the cold water? 8.3 °C
2. What was the temperature decrease of the warm water? 8.3 °C
3. What is the ratio of the warm water temperature decrease to the cold water temperature increase?
8.3/8.3 = 1
Share this on the data table on the board.
4. How does this compare with the group?
PART 2:
1. Calculate the ratio of the warm water to the cold water. Record in table below.
2. State the reciprocal of the ratio of masses. Record in table below.
3. Calculate the decimal equivalent of reciprocal of ratio of masses. Record in table below.
4. Calculate the ratio of the temperature changes (decrease/increase). Record in table below.
Trial
Ratio of
Masses
(Warm/Cold)
Reciprocal of
masses
Decimal
Equivalent of
Reciprocal
Ratio of
Temperature changes
(decrease/increase)
1
2
½
0.5
4.6/8.7 = 0.53
2
4
¼
0.25
3
5
1/5
0.2
Which of the two masses underwent the larger temperature change (the larger or smaller mass)?
smaller
How does the decimal equivalent of the reciprocal of the masses compare to the ratio of temperature changes?
Physical Science Institute
Summer 2013
They are the same.
Is there a relationship between the warm water mass and temperature decrease, and the cold water mass and its
subsequent temperature increase? Represent this relationship as a mathematical equation.
(Mwarm water)(Tdecrease) = (Mcold water)(Tincrease)
We can now use this product to define the change in thermal energy. With this definition, the increase in thermal
energy of the cool water equals the decrease in thermal energy of the warm water. In order to define this as an amount
of energy, a unit of energy must be chosen. In this case, the unit is: (g)(Δ⁰C)
This is also the definition of the calorie,
the standard unit of energy used in food energy.