Measurements and Chemical Reactions
In a chemical reaction, the chemicals you start with are called the REACTANTS. The chemicals produced
during the reaction are called the PRODUCTS.
REACTION BETWEEN METALLIC ALLUMINUM AND COPPER CHLORIDE SOLUTION
1. BEFORE going to the lab station, put on a lab apron and goggles
2. Working in pairs, measure about 20 millilters (mL) of copper (II)
chloride solution into a graduated cylinder. Record the exact
volume in the data table below.
3. Pour the copper chloride solution into the beaker.
4. Measure and record the temperature of the copper chloride.
5. Crumple the aluminum foil and drop it into the copper chloride solution.
6. Observe the reaction for 5-10 minutes and record your observations.
7. Record the highest temperature the solution reaches. Don’t let the thermometer and beaker tip over!.
8. Clean up: Empty the beaker into the waste container under the fume hood. Wipe off you work area with a
paper towel. Wash your hands. Return your apron and goggles to their correct locations.
Data: (DON’T FORGET UNITS)
Volume of Copper (II) Chloride solution in the graduated cylinder
Initial temperature of solution
Final temperature of the solution
Observations:
Describe the two reactants of this reaction:
1.
2.
Describe the three products of this reaction.
1.
2.
3.
Chemical reactions that give off heat are called EXOTHERMIC. Below is the energy diagram of an exothermic
reaction. At the end of the reaction (right side of the diagram) the products have lost some of their potential
energy in the form of heat:
Chemical reactions that absorb heat are called ENDOTHERMIC. These reactions feel cold because they are
pulling heat out of your hand. If you put a thermometer into them they pull heat out of the thermometer,
causing the temperature to go down. Below is the energy diagram for an endothermic reaction:
Was the reaction between aluminum foil and copper (II) chloride solution exothermic or endothermic? Explain
your answer.