Name: __________________________________ Date: __________________ Period: ________
Types of Reactions
Purpose: To investigate the characteristics of the four main types of
chemical reactions.
Safety:
1.
2.
3.
4.
5.
Wear goggles throughout the activity!
Carefully follow instructions for disposal of used chemicals.
Extinguish flames when you are not using them.
Avoid breathing in vapors over test tubes or containers of chemicals.
Use caution when handling HCl.
Procedure: Before beginning the laboratory work, read through the entire
procedure for each part of the activity. Record what you observe for each
activity. Answer the questions for each part of the lab.
Part 1:
Materials: Small piece of copper or steel wool, tongs, burner, watch glass.
1. Obtain a piece of copper or steer wool.
2. Weigh the wool on the balance using a watch glass. (Record mass
below in grams.)
3. Light the burner, and using a pair of tongs, hold the wool in the flame
for about 5 minutes. (Record your observations below.)
Observations:
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4. After heating, allow the wool to cool and place it back in the weighing
dish.
5. Re-weigh the burnt wool. (Record mass below in grams.)
6. Describe the appearance of the burnt wool.
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Substance
Unburnt Wool
Burnt Wool
Change in Mass
Mass in grams
Name: __________________________________ Date: __________________ Period: ________
The chemical equation for this reaction is: 2Cu + O2 → 2CuO
1. What type of reaction is this? _______________________________
2. What evidence do you see that a chemical reaction has taken place?
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3. Why does the mass change?
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Part 2:
Materials: CuSO4•5H2O (Copper Sulfate Pentahydrate), burner, test tube +
rack, dropper.
1. Put a small amount (size of a lima bean) of CuSO4•5H2O in a test
tube.
2. Weigh the test tube with the compound in it together on the balance.
(Record the mass below in grams.)
3. Using a test tube holder, tilt the test tube so that the compound
spreads out a little.
4. Using the holder, hold the test tube nearly horizontal (↔), not toward
anyone, and move it back and forth through the top part of the flame
so that the entire compound is heated. Heat the compound very
gently for about 2 minutes. Do not heat it too much as it may spatter.
If it starts to turn dark you have heated it too much.
5. What happens to the appearance of the compound as it is heated?
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6. Allow the test tube and compound to cool for a few minutes, then
reweigh it and record the mass after heating.
Mass of test tube + compound
before heating (In Grams).
Mass of test tube + compound after
heating (In Grams).
Name: __________________________________ Date: __________________ Period: ________
7. Use your dropper and add a drop or two of water to the compound in
the test tube. What happens?
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8. Carefully rinse the compound down the sink.
The chemical reaction that takes place during heating is:
CuSO4•5H2O → CuSO4 + 5H2O
1. What type of reaction is this? _______________________________
2. What evidence did you see that a chemical reaction has taken place?
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3. Why does the mass change when you heat the compound? (Hint:
What substance is “leaving?”)
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Part 3:
Materials: Hydrochloric Acid (HCl), CuSO4, small piece of solid zinc, small
strip of magnesium, 2 test tubes, test tube holder, graduated cylinder.
1. Place about 5 mL of HCl in one of the test tubes. Add a piece of zinc
metal (Zn). What happens?
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2. Wait about 5 minutes and observe the test tube again. What has
happened?
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3. Place about 5 mL of the CuSO4 solution in the second test tube. Add
a strip of magnesium (Mg). What happens?
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Name: __________________________________ Date: __________________ Period: ________
4. Wait about 5 minutes and observe the test tube again. What has
happened?
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***Empty the test tube down the drain.***
The chemical equation for the first reaction you observed is:
Zn + 2HCl → ZnCl2 + H2
1. What type of reaction is this? _______________________________
2. What evidence do you see that a chemical reaction has taken place?
_______________________________________________________
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3. What is the gas that is formed during the reactions? _____________
...and for the second reaction:
Mg + CuSO4 → MgSO4 + Cu
4. What type of reaction? ____________________________________
5. What evidence do you see that a chemical reaction has taken place?
_______________________________________________________
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6. How can you tell that Cu metal is a product of this reaction?
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Part 4:
Materials: Two test tubes, barium chloride BaCl2, sodium sulfate Na2SO4,
cobalt nitrate Co(NO3)2, and sodium phosphate Na3PO4.
1. Place about 3 mL of the BaCl2 in the first test tube. Add about 3 mL
of the Na2SO4. What happens?
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2. Place about 3 mL of the Co(NO3)2 in the second test tube. Add about
3 mL of the Na3PO4. What happens?
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***Dispose of the contents in the chemical waste container.***
Name: __________________________________ Date: __________________ Period: ________
The chemical equation for the first reaction is:
BaCl2 + Na2SO4 → 2NaCl + BaSO4
1. What type of reaction is this? _______________________________
2. What evidence did you see that a chemical reaction has occurred?
_______________________________________________________
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The chemical equation for the second reaction is:
3Co(NO3)2 + 2Na3PO4 → Co3(PO4)2 + 6NaNO3
3. What type of reaction is this? _______________________________
4. What evidence did you see that a chemical reaction has occurred?
_______________________________________________________
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Conclusion Questions:
1. Classify the following chemical reactions as synthesis,
decomposition, single replacement, or double replacement.
a. NaCl + AgNO3 → AgCl + NaNO3 ________________________
b. 2Mg + O2 → 2MgO __________________________________
c. 2HgO → 2Hg + O2 ___________________________________
d. 2Al + 3CuSO4 → Al2(SO4)3 + 3Cu _______________________
2. In this lab, you were given the chemical equations for the reactions.
Assuming you didn’t have this information, do you think it is possible
to classify a chemical reaction just from observation? Explain...
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3. List some things you can think of that might be helpful to you in
classifying a reaction you observe.
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