1. 14.1 & 14.4 Test Review
Answer Key

2. 1. What are the 4 signs that a chemical reaction May have taken place?
Solid formation
Gas formation
Energy change
Color change

3. 2. What is the proof that a chemical reaction has taken place?
Formation of new substances

4. 3. Give three examples of a chemical reaction.
Burning wood
Glow stick glowing
Flashlight shining
Rusting metal
Leaves changing color

5. 4. What are three sources of activation energy
4. What are three sources of activation energy? Give an example of a chemical reaction that uses each.
Light – breaking down of hydrogen peroxide
Electrical spark – spark plug ignites gas in a car
Friction – striking a match catches it on fire

6. 5. How do substances form during a chemical reaction?
Bonds in reactants are broken, atoms rearrange, and new bonds are formed to create new substances.

7. 6. What are the five factors that affect the rate of reactions?
Temperature
Concentration
Surface area
Catalyst
inhibitor

8. 7. Name 3 ways to increase the rate of reaction.
Increase temperature
Increase concentration
Increase surface area
Add a catalyst

9. 8. What is necessary for bonds to break?
Energy from molecules bumping into each other

10. 9. Name 3 ways to slow down a chemical reaction.
Decrease temperature
Decrease concentration
Decrease surface area
Add an inhibitor

11. 10. What is activation energy?
The minimum amount of energy required for a chemical reaction to start.

12. 11. Give an example of an exothermic reaction.
Burning wood
Glow stick glowing

13. 12. Give an example of an endothermic reaction.
Photosynthesis

14. From broken bonds in the reactants
13. From where does the energy released in an exothermic reaction come?
From broken bonds in the reactants