Chemistry: Calorimetry Lab
Mr. Puckett
Name___________________________Date_______
Per__________________
Purpose: This lab is designed to use calorimetry calculations and temperature measurement to measure
the caloric content of different foods.
1. Pre Lab Questions
a. What is a calorie?
b. What is the difference between a calorie in science and a Calorie in food?
c. How many joules are in a calorie? How joules are in a Calorie?
d. How is the calorie count of a particular food measured experimentally?
e. 250 ml of water is heated from 30 °C to 41.2 °C. How much heat did the water
absorb/release? Was the heat absorbed or released (pick one)?
f.
Observe the dry food products you’ll be burning. Which do you think should have the
highest calorie content? The lowest?
2. Materials
-
dry food products
Graduated cylinder
aluminum soda can
pencil or pen that will fit through the tab on the soda can
lighter or matches
Bunsen burner stand and grate
thermometer
ring stand
3. Procedure
a. Weigh a small, single piece of food sample (1 chip, 1 almond, etc) and record the food
sample and weight in the table below.
b. Place the sample on the bunsen burner stand and grate
c. Weigh the soda can before and after putting in about 60 mL of water and record the
masses below
d. Measure and record the initial temperature of the water
e. Hover the can above your sample using a ring stand
f. Light your sample on fire using matches or a lighter and slide the can over the sample
such that all of the heat is rising into the can as seen below
g. Once the flame has gone out, immediately measure and record the temperature of the
water.
h. repeat the whole process (a-g) for 5 different food samples.
Sample
Mass of sample
(g)
Mass of can (g)
Mass of can +
water (g)
initial temp
final temp
4. Post Lab Questions
a. Calculate the energy input to the water (q) in each of the 5 samples.
b. Convert these results to calories (1 cal = 4.18 J). Convert them to kcal (1 kcal = 1000 cal)
c. Divide the energy (q) by the mass of the sample for each one to end in units of Cal/g.
Sample
Mass of
sample (g)
q (J)
q (cal)
q (kcal)
Energy content
(kcal/g)
d. Create a bar graph comparing the different food types in the table below by coloring in the
cells to indicate each bar.
10 Cal/g
5 Cal/g
0 Cal/g
Foods:
e. Are these results surprising? Which ones did you expect to have the highest calorie
content and why?
f.
What sources of error (there’s a lot of them) could we have had during this lab?
g. What could be done to minimize sources of error?