Chemistry Laboratory – Dr. May
Single Displacement Reactions
Introduction:
All elements occur in nature as free (uncombined) or chemically combined in a
compound. The tendency of an element to combine with other substances is a measure of
the activity of that element. In single-replacement reactions, an uncombined element
replaces a less active one that is combined in a chemical compound. The less active
element is then freed from the compound.
For example, in the reaction
Zinc + Copper sulfate  Zinc sulfate + Copper
Zn
+
CuSO4

ZnSO4
+
Cu
Zinc replaces the less active copper, combines with the sulfate, and frees the
copper from the compound.
In this laboratory investigation we will observe how various metals undergo
single-replacement reactions when placed in acid or in a solution of a salt of a less active
metal. If the metal is more active than the hydrogen in the acid, it will replace the
hydrogen and hydrogen gas will be released. If the metal is more active than the metal in
the salt, the metal in the salt will be deposited as a metal.
Objective:
Determine the activity of various metals relative to hydrogen by deciding if the
metal replaces the hydrogen from hydrochloric acid. Determine the activity of various
metals relative to other metals by deciding if the metal replaces the metal from the salt.
Procedure:
1.
2.
3.
4.
5.
6.
7.
Put on safety goggles upon entering the laboratory.
Label each test tube with the reaction number from page 2.
Carefully pour about 1 inch of 1 M hydrochloric acid into the first 4 test tubes.
One at a time, place the appropriate metal in each test tube.
Carefully pour about 1 inch of the appropriate salt solution into the last 3 test tubes.
Place a metal into the solution and observe the reaction.
Observe what happens to the metal in each test tube and feel each test tube as the
reaction proceeds.
8. Record your data in the Observations Section below.
1
Observations:
1. Magnesium + HCl
2. Aluminum + HCl
3. Zinc + HCl
4. Iron + HCl
5. Copper + Silver nitrate
6. Iron + Copper chloride
7. Aluminum + Copper sulfate
2
Analysis and Conclusions:
Write the single-replacement reaction that occurred between the acid and each metal.
1. Magnesium + HCl
2. Aluminum + HCl
3. Zinc + HCl
4. Iron + HCl
5. Copper + silver nitrate
6. Iron + Copper chloride
7. Aluminum + Copper sulfate
8. Sodium + water
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Critical Thinking and Application:
1. What happened when Dr. May placed magnesium into water ?
2. What happened when Dr. May placed sodium into water ?
3. How could you prove that hydrogen gas was produced as a result of a reaction?
4. What is formed when hydrogen gas is burned ?
Activity series of metals
(Most) ↴
Li, K, Ca, Na, Mg, Al, Zn, Cr, Fe, Ni, Sn, Pb, H, Cu, Hg, Ag, Pt, Au ↰
(Least)
5. Which elements above will not react with HCl ?
6. Which elements above will not react with CuSO4 solution ?
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