1. Endothermic Exothermic LAB

2. Pre-lab
Endothermic reaction: chemical reaction that takes in heat energy
Energy of reactants < Energy of products
Exothermic reaction: chemical reaction that releases heat energy
Energy of reactants > Energy of products

5. Pre-lab
Activation Energy: amount of energy needed to break old bonds and make new ones
Catalyst: lowers the activation energy needed for a reaction to go

7. Supplies/ Materials Ziplock bag Calcium Chloride Vitamin C powder
Measuring tools
Phenol red indicator
Baking soda
Water

8. Procedure/ Method Reaction #1
Measure 1 tsp baking soda, 1 tsp vitamin c, 15mL water
In ziplock bag, mix dry solids together first. Then add water. Gently mix. Then close bag. Record observations.
*WARNING: bag may not be large enough for reaction. Carefully open bag as needed.

9. Procedure/ Method Reaction #2
Empty contents from bag into sink. Rinse bag out with water until clean.
Measure 1 tsp baking soda, 1 tsp calcium chloride, 10mL phenol red

10. Procedure/ Method Reaction #2
In ziplock bag, mix solids first. Then add phenol red. Gently mix. Then close bag. Record observations.
*WARNING: bag may not be large enough for reaction. Carefully open bag as needed.
4) Throw bag away in trash can by the door

11. Data Table COOLER OR WARMER AFTER MIXING? SIGNS OF CHEMICAL REACTION

12. Post-lab
Which reaction (#1 or #2) was the exothermic reaction? How could you tell? You don’t have to copy this slide down, but please answer in complete sentences.