My PBL Project

Al displaces Cu

Introduction

In the project I am going to see how Al (aluminum) displace Cu(copper) by displacement.

Materials

  • Beakers, Pyrex®, 600-mL, 3

  • Graduated cylinder, 250-mL

  • Spatula

  • Stirring rod

  • Thermometer (or Temp Probe)

  • Wood splint and matches

  • Aluminum foil, 6" x 12", 2 pieces

  • Copper(II) chloride solution, CuCl2, 1.0 M, 140 mL

  • Copper(II) sulfate solution, CuSO4, 1.0 M, 140 mL

  • Sodium chloride solution, NaCl, 1.0 M, 140 mL*

  • Water, distilled, 420 mL

Procedures

Section 1: Aluminum and Copper(II) chloride

1. Place a 600-mL Pyrex® beaker on the work table.

2. Use a graduated cylinder to measure 140 mL of 1.0 M CuCl2 solution. Pour this

solution into the beaker.

3. Measure and add 140 mL of distilled water to the beaker. The solution is now 0.5 M

CuCl2 solution.

4. Cut a piece of aluminum foil approximately 6" x 12". Loosely crumple the foil enough

to fit into the beaker but do not crush the foil tightly into a ball as this will slow the

reaction and much of the aluminum will remain unreacted.

5. Measure the temperature of the CuCl2 solution before adding the foil.

6. Place the piece of crumpled foil into the beaker. Using a stirring rod, push it down

completely into the solution. Measure the temperature of the reaction mixture again.

7. Observe all changes that occur including a change in temperature. Record your

observations/data in detail.

8. Discuss if a reaction occurred and what are the reactants and products based on

your observations. Also discuss if the reaction is exothermic or endothermic. Test

your hypothesis about the identity of the products and reactants in this reaction by

conducting Section 2.

Section 2: Aluminum and Copper(II) sulfate

9. Repeat the procedure (steps 1-8) from Section 1 in a different 600-mL beaker,

except this time using 70 mL of 1.0 M CuSO4 solution and 70 mL of distilled water.

The solution is now 0.5 M CuSO4.

10. Discuss if a reaction occurred and what are the reactants and products based on

your observations. Also discuss if the reaction is exothermic or endothermic. Test

your hypothesis about the identity of the products and reactants in this reaction by

conducting Section 3. : Set the beaker from Section 2 aside for use in Section 4.

Section 3: Aluminum and Sodium chloride

11. Repeat the procedure (steps 1-8) from Section 1 in a different 600-mL beaker,

except this time using 70 mL of 1.0 M NaCl solution and 70 mL of distilled water.

The solution is now 0.5 M NaCl

12. Discuss if a reaction occurred and what are the reactants and products based on

your observations. Also discuss if the reaction is exothermic or endothermic. Test

your hypothesis about the identity of the products and reactants in this reaction by

conducting Section 4. Set the beaker from Section 3 aside for use in Section 4.

Section 4: Aluminum and Copper(II) Sulfate and Sodium Chloride

13. Place the beaker from Section 2 on the work table.

14. Add 70 mL of 1.0 M NaCI solution and 70 mL of distilled water to the beaker.

15. Discuss the role of various chemicals in the reaction and if the hypotheses put forth

in previous sections was validated or disproved based on observations and data.

16. Write the chemical equation for the reaction. If chloride ions are not in the equation,

what is the purpose of the chloride ions? Discuss the role of a catalyst in a reaction.

Predict what would happen if CuSO4 were added to the beaker from Section 3.

17. Then, try it out. Place the beaker from Section 3 on the work table. This beaker

contains the unreacted aluminum foil in the 0.5 M NaCI solution.

18. Add 70 mL of 1.0 M CuSO4 solution and 70 mL of distilled water to the beaker.

19. Discuss observations and hypotheses about the identity of the products and

reactants in this reaction. Write chemical equations and your explanations for the

reactions.

Scientific Principle

Chemical reactions (single displacement) causing change and forming a new compound; changing temperature, color, and odor.

  • The reaction of certain elements with each other causes them to go through a chemical reaction known as displacement.

e.g.

Any metal that is higher in the "electromotive series" will displace copper sulphate. Aluminum, is an example of that.

*electromotive series: any element who has a tendency to give up electrons.

CuSO4(aq) + Al(s) ----> Al2SO4(aq) + Cu(s)

Safety Precautions

Copper( II) chloride solution and copper( II) sulfate solution are toxic by ingestion. Small

quantities of hydrogen gas are produced from the reaction. Hydrogen is a highly flammable

gas; keep flammable materials away from the reaction mixture. Wear chemical splash

goggles, chemical-resistant gloves, and a chemical-resistant apron. This activity requires

the use of hazardous chemicals and/or has the potential for hazardous reactions. Please

review the Safety Precautions section and relevant Material Safety Data Sheets before

beginning this activity.