Name______Period______Date______Name______Period______Date______Endothermic and exothermic reactions LAB Background A reaction in which heat energy is released is called an exothermic reaction. A reaction in which heat energy is absorbed is called an endothermic reaction. Materials Ziplock bag, calcium chloride (CaCl2), sodium bicarbonate (NaHCO3), water (H2O), and phenol red. Procedure and observations 1. Mix calcium chloride with phenol red solution. Record at least three observations of what happens when chemicals are mixed.

2. Mix sodium bicarbonate with phenol red solution. Record at least three observations of what happens when chemicals are mixed.

3. Mix mixture #1 (calcium chloride and phenol red solution) and mixture #2 (sodium bicarbonate and phenol red solution). Record at least three observations of what happens when chemicals are mixed.

Discussion 1. Identify what reaction in your experiment was an endothermic reaction.

2. Identify what reaction in your experiment was an exothermic reaction 3. Name at least three signs of chemical reaction that you observed in this lab

Constructing a Double Bubble Map

Find the similarities (at least three) and differences (at least three) between an exothermic reaction and endothermic reaction.

Exothermic Endothermic reaction reaction