7.              Look at the TABLE data, NOT THE GRAPH data.  Press the S button ON THE TABLE.  On the bottom of your TABLE, different statistics will appear.  The “min” value is your temperature before burning. The “max” value is the temperature after burning.  Record this min and max data in a chart that resembles the one below.

 

8.              Zero or tare the balance before you attempt to measure the final mass of the remains of the burned food sample.  CAUTION:  It’s hot; if necessary , use tongs to remove the can and tweezers to remove the sample.

 

9.              Repeat the data recording process for the walnut and cashew, after you have done all three types of nut, repeat.  Try and do at least two runs per nut type, three runs would be great!

 

10.           To calculate the calories, Kcals and Kcals per gram, use the equations on the previous page.

 

 

Data

Cashew 1

Cashew 2

Peanut 1

Peanut 2

Walnut 1

Walnut 2

Mass of sample before burning

 

 

 

 

 

 

Mass of sample after burning

 

 

 

 

 

 

Change in sample mass

 

 

 

 

 

 

Temperature before burning (min)

 

 

 

 

 

 

Temperature after burning (max)

 

 

 

 

 

 

Change in temperature

 

 

 

 

 

 

calories

 

 

 

 

 

 

Kcal

 

 

 

 

 

 

Kcal per gram

 

 

 

 

 

 

Average Kcal/g

XXXXX

 

XXXXXX

 

XXXXXX

 

Analysis Questions:

1.     Food energy is expressed in a unit called a Calorie. Calculate the number of calories in your sample using the first equation in the background information (Eq. 1).  Calculate the number of Kcals in your sample using Eq. 2.  Calculate the number of Kcal per gram in your sample by dividing the Kcals by the change in grams of your sample (Eq. 3).  Determine the average Kcal/gram for your samples.  Remember, (D means “change in”).  Determine the average Kcal/gram for your samples. Record all of this information in your data chart.

 

2.     Your  average Kcal/gram data for each type of nut is what % of the actual values listed below for peanuts, walnuts, and for cashews?

·       Peanuts- 6.0  kcal/gram

·       Walnuts- 7.02 kcal/gram

·       Cashews- 6.0 kcal/gram

 

 

3.     Refer back to the background information in this handout, think back to the verbal information your teacher told you about our calorimeters compared to an actual calorimeter laboratory.   How do your account for any differences in your recorded values and the listed values?

 

4.     What advice would you give to a sports team about the energy content of these foods, which nut was the highest in energy according to your data, according to the actual listed data?

 

5.     What are some things you would do to change our procedure in this activity to make it more accurate; that is to obtain data that is closer to the listed values given above?

 

6.     In this ecosystem; what is the ORIGINAL source of energy in all the foods tested?  (Hint: they  are all plant products)