Question

1. How does the amount of energy in the batteries in a flashlight compare to the total amount of energy given off by the flashlight as light and heat?
2. What are two ways the rate of a chemical reaction can be changed?
3. Imagine you chew a cracker and swallow it.
a. What role does saliva play?
b. How is energy stored in a cracker?
c. How is energy released from the cracker?

Answer 1

1. The total energy in the batteries and the total energy given off by the flashlight through heat and light is equal. This is because of the "Law of the Conservation of Energy." Energy cannot be created or destroyed, only changed in form. This can also be backed with the first law of thermodynamics.

2. A rate of a chemical reaction can be increased by increasing the temperature, or introducing a catalyst.

3. a. The saliva acts as a catalysts in breaking down the cracker.

3. b. The energy is stored in the chemical bonds on the sugars in the cracker.

3. c. The energy is the cracker is released through the body's natural process in breaking down the cracker and the sugars.