1. Section B Intro to Lab Activity B.1
Food as Energy
Section B
Intro to Lab Activity B.1

2. Food as Energy All human activity requires Not really burned
Burning food for energy
Not really burned
Energy is released by chemical rxn’s
How can we Tell??

3. Figuring how much energy…
How to determine amount of energy
Burn a known amount of food
Carefully measure quantity of thermal energy released
=CALORIMETRY
Calorimeter is the device we use!!!

4. Units of Energy calorie Calorie
Thermal energy needed to raise the temp. of 1 gram of water 1 degree Celsius
Calorie
1000 calories
Increases the temperature of 1kg of water by 1 degree Celsius
1,000 calories (cal) = 1 kilocalorie(kcal) = 1 Calorie (Cal)

5. Importance of Calories
Nutritionists
Count Calories
Dieting
Comparing foods

6. Where does food energy originate?
All food energy comes from sunlight
Plants capture solar energy
Make large energy rich molecules
Energy converted to chemical energy
We recover this energy when we eat plants or animals that eat these plants

7. So Why is this all Important?
Determine energy given off by a peanut when it burns
Oil in peanuts burns fast when
Your peanut will heat a known mass of water
You will measure the temp of the water before and after
Then you will calculate the thermal energy
From that we can determine the calories in that peanut!!

8. Page 239-241 Food Energy in A Peanut