Rxn Types 1
Name ______________________________________________ Date _________ Period ______
Types of Chemical Reactions
Purpose
After reading the lab, create your own purpose below:
______________________________________________________________________________
______________________________________________________________________________
Pre-Lab Discussion (Do not copy in your lab book)
Chemical reactions occur when substances change identity. There are many signs of
chemical reactions, including precipitate formation, color changes, temperature changes, gas
evolution and more. Most reactions can be classified into five major categories: Synthesis,
Decomposition, Single Replacement, Double Replacement, or Combustion. In this lab, you will
witness each reaction type, to determine any similarities or differences between the types.
Materials
Bunsen Burner
Crucible Tongs
Matches / Striker
Microspatula
Pipets
Test Tubes and Rack
Test Tube Holder
Wooden Splints
Copper Wire (Cu)
Manganese (IV) Oxide (MnO2)
Sodium Bicarbonate (NaHCO3)
Zinc (Zn)
5 % Acetic Acid (HC2H3O2)
0.1 M Calcium Chloride (CaCl2)
1 M Copper (II) Sulfate (CuSO4)
6 M Hydrochloric Acid (HCl)
3% Hydrogen Peroxide (H2O2)
1 M Silver Nitrate (AgNO3)
Procedure
Station 1 – Synthesis
1. Take a piece of Copper wire and note its appearance in the Data section.
2. Using crucible tongs, hold the wire in the hottest part of a burner flame for 1-2 minutes.
DO NOT LET THE WIRE MELT!
3. Examine the wire and record any change in its appearance caused by heating under Data.
Station 2 – Decomposition
4. Add 2 pipets (~10 mL) of Hydrogen Peroxide (H2O2) to a test tube. Record “Before”
observations in Data section.
5. If not already present in the test tube, add a small scoop of Manganese (IV) Oxide
(MnO2) to the test tube.
6. As the reaction occurs, light a wood splint and allow it to burn freely for 5 seconds.
7. Blow out the splint flame and place the glowing splint into the test tube to test the
identity of the gas formed. Record all observations in the Data section.
8. Decant the liquid. The MnO2 is a catalyst, and can be reused by other groups. Leave the
MnO2 in the test tube.
Rxn Types 2
Station 3 – Single Replacement
9. Stand a clean, dry test tube in the test tube rack. Add 2-3 pipets
of Hydrochloric Acid (HCI) to the tube.
10. Obtain a small piece of Zinc shot (Zn) and record “Before”
observations of both materials in Data section. Drop the Zn into
the HCl in the test tube.
11. Using a test tube holder, invert a second test tube over the
mouth of the test tube in which the reaction is taking place. See
Figure 1.
12. After about 30 seconds, remove the inverted tube and quickly
insert a burning wood splint into the mouth of the tube. Record
all observations in the Data section.
Figure 1
Station 4 – Single Replacement / Double Replacement
13. Add 2 pipets (~10 mL) of copper (II) sulfate (CuSO4) to a test tube.
14. Obtain a small piece of Zinc shot (Zn) and record “Before” observations in Data section.
Drop the Zn into the CuSO4 in the test tube.
15. Observe the reaction for 2-3 minutes. Record all observations in the Data section.
16. While waiting on the first reaction, add 1 pipet (~5 ml) of Silver Nitrate (AgNO3) in a
test tube. Record “Before” observations in Data section.
17. Add 1 pipet (~5 ml) of Calcium Chloride (CaCl2) in the test tube. Record all observations
in the Data section.
Station 5 – Double Replacement
18. Place a small scoop of Sodium Bicarbonate (NaHCO3) in a test tube. Record “Before”
observations in Data section.
19. Add 2 pipets (~10 mL) of acetic acid (HC2H3O2) to the test tube.
20. Light a wood splint and place it in the mouth of the test tube to test for Carbon Dioxide
gas. (Note: If the flame goes out, CO2 is present.)
21. Record all observations in the Data section.
Station 6 – Combustion
22. Light the Bunsen burner. (CH4, methane, is the flammable gas in the Bunsen burner)
23. Record “Before” observations of the test tube in Data section.
24. Using a test tube holder, invert a clean, dry test tube over the flame. Look for evidence of
water production in the test tube.
25. Light a wood splint and place it in the mouth of the test tube to test for Carbon Dioxide
gas. (Note: If the flame goes out, CO2 is present.)
26. Record all observations in the Data section.
Rxn Types 3
Data (Cut and tape in lab notebook)
Table 1 – Reaction Observations
Station
Substances
1
Cu + O2
2
H2O2
3
Zn + HCl
Before Reaction
Zn + CuSO4
4
AgNO3 + CaCl2
5
NaHCO3 + HC2H3O2
6
CH4 + O2
Questions
1. For each step, explain how you knew a chemical reaction occurred.
After Reaction
Rxn Types 4
2. In this lab, what was a positive test for the presence of CO2 gas? How is a positive test for
CO2 different than a positive test for O2? Why do you think this is?
3. How did you test for hydrogen gas? How did you know when it was present? What
would the hydrogen react with to cause the positive test?
Conclusion
Were the signs of a chemical change different for each reaction type? Do you think you could
identify the type of a reaction based solely on the signs of a chemical change you observe in a
reaction? Use observations to justify your answer.