Experiment 9
Name: _________________________
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AC Ti VITY S Er IES
In this experiment, you will observe single displacement reactions that occur when a metal is
oxidized by salts (or ionic compounds) and by acids. You will also learn to use the activity series
to predict if a single displacement metal-salt or metal-acid reaction occurs or not.
Oxidation of Metals
Single displacement reactions conform to the general pattern:
A + BX → AX + B
The cation, Bn+, in solution is said to be displaced by the element A as it oxidizes to Am+.
When copper, a reddish-brown metal reacts with colorless silver nitrate solution, a gray
solid deposits and the solution turns blue, due to the products silver and copper(II) nitrate. Cu
displaces Ag.
Cu(s) + 2AgNO3(aq) → Cu(NO3)2(aq) + 2Ag(s)
reddish-brown
metal
colorless
solution
blue
solution
gray
metal
The complete and net ionic equations for this reaction are:
Cu(s) + 2Ag+(aq) + 2NO3-(aq) → Cu2+(aq) + 2NO3-(aq) + 2Ag(s)
Cu(s) + 2Ag+(aq) → Cu2+(aq) + 2Ag(s)
The net ionic equation shows that this reaction is a redox reaction, with the oxidation number of
Cu increasing from 0 to +2 and that of Ag decreasing from +1 to 0. Cu is oxidized by Ag+ in
the salt solution.
When manganese is allowed to react with hydrobromic acid, bubbles appear due to the
formation of hydrogen gas as Mn displaces H.
Mn(s) + 2HBr(aq) → MnBr2(aq) + H2(g)
The complete and net ionic equations for this reaction are:
Mn(s) + 2H+(aq) + 2Br-(aq) → Mn2+(aq) + 2Br-(aq) + H2(g)
Mn(s) + 2H+(aq) → Mn2+(aq) + H2(g)
Mn is oxidized by H+ in the acid. The oxidation number of Mn increased from 0 to +2 and that
of H decreased from +1 to 0.
 Dr. Gloria Pimienta
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Activity Series
Elements differ in their ability to displace other elements. For example, Cu can displace
Ag but Ag can not displace Cu.
Cu(s) + 2Ag+(aq) → Cu2+(aq) + 2Ag(s)
Ag(s) + Cu2+(aq) → No reaction
H can oxidize Mn but not Au.
Mn(s) + 2H+(aq) → Mn2+(aq) + H2(g)
Au(s) + H+(aq) → No reaction
The activity series allows for the prediction whether or not a single displacement reaction will
occur. The activity series shown here lists the elements from the most active to the least active,
that is, from the easiest to oxidize to the hardest:
Li > K > Ba > Ca > Na > Mg > Al > Mn > Zn > Cr > Fe >
Co > Ni > Sn > Pb > H > Cu > Ag > Hg > Pt > Au
An element can be oxidized by the ions of the elements below it in the activity series.
For example, Ag is below Cu so Ag can oxidize Cu to Cu2+. In other words, Cu displaces Ag in
the salt solution because it is easier to oxidize Cu than Ag. H is below Mn in the series but
above Au, thus it can oxidize Mn (to Mn2+) but not Au.
PROCEDURE
I. Oxidation of Metals by Salts
1. Make initial observations on the appearance of the metals Mg, Fe, Cu and Zn.
2. Make initial observations on the appearance of the solutions of Mg(NO3)2, Fe(NO3)3,
Cu(NO3)2 and Zn(NO3)2.
3. Obtain four test tubes and to each one, add 5-10 drops of one of the solutions. Set
these aside. They will be used as reference for solution color changes that may occur
during reaction by placing the solutions against a white background.
As a general overview of how to proceed, refer to the data table in your worksheet.
In a test tube, a metal and a salt solution are allowed to react, corresponding to one
cell in the table where you will note your observation. The reaction of a metal with
its own solution is omitted as designated by X marks. Complete one metal (one
row) at a time.
 Dr. Gloria Pimienta
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4. Obtain three test tubes. To each, add a small sample (spatula-tip full for powder) of the
metal. To each test tube, add 5-10 drops of a solution. Observe any changes to the
metal and solution, referring to the unreacted metal and to the reference solutions
prepared in Step 3 if needed. Note the intensity and reaction rate (fast or slow). Write
NR for no reaction.
5. Dispose of the wastes in the container designated for the metal. Wash the test tubes,
shake off any excess water then proceed to the next metal. Work with one metal at a
time to ensure you do not lose track of the test tube contents for proper waste disposal.
6. Upon completion of all the metal-salt solution combinations, dispose of the reference
solutions and wash all test tubes.
II. Oxidation of Metals by Hydrochloric Acid
1. Obtain four test tubes. To each, add a small sample of each metal.
2. Add 5-10 drops of 6 M HCl solution to each test tube. Watch for appearance of
bubbles. Note the intensity and reaction rate (fast or slow). Write NR for no reaction.
CLEAN-UP


Dispose of wastes in designated containers in the front hood.
Wash all test tubes. Shake off excess water and return to the test tube racks on your
work station.
 Dr. Gloria Pimienta
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Name: ___________________________________
Partner’s Name: ___________________________
ACTIVITY SERIES
DATA AND OBSERVATIONS
I. Oxidation of Metals by Salts
A. Initial Observations
Metals
Mg
_____________________________
Fe
_____________________________
Cu
_____________________________
Zn
_____________________________
Solutions
Mg(NO3)2
_____________________________
Fe(NO3)3
_____________________________
Cu(NO3)2
_____________________________
Zn(NO3)2
_____________________________
 Dr. Gloria Pimienta
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Date: ____________________
B. Reactions
Solutions
Metals
Mg(NO3)2
Mg
Fe(NO3)3
Cu(NO3)2
X
Fe
X
Cu
X
Zn
II.
X
Oxidation of Metals by Acid
Observations
Mg + HCl
__________________________________
Fe + HCl
__________________________________
Cu + HCl
__________________________________
Zn + HCl
__________________________________
 Dr. Gloria Pimienta
Zn(NO3)2
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POST-LAB QUESTIONS
1. Did you observe any experimental results that are inconsistent with the activity series
(for example, a metal-salt combination supposed to react did not or not supposed to
react but did)? State which ones. What factors or specific human errors may explain
these unexpected results?
2. For the metals that reacted with HCl in Part II of the experiment, write the balanced
chemical equation and the complete and net ionic equations. For the metals that did not
react, write NR.
a. Mg
Balanced chemical equation:
Complete ionic equation:
Net ionic equation:
b. Fe (+3 charge on Fe for the product)
Balanced chemical equation:
Complete ionic equation:
Net ionic equation:
 Dr. Gloria Pimienta
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c. Cu
Balanced chemical equation:
Complete ionic equation:
Net ionic equation:
d. Zn
Balanced chemical equation:
Complete ionic equation:
Net ionic equation:
3. Predict if a reaction occurs between Pb(NO3)2 and the following metals. If a reaction
occurs, write the balanced chemical equation and the net ionic equation. If a reaction
does not occur, write NR.
a.
K
Balanced chemical equation:
Complete ionic equation:
Net ionic equation:
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b. Au
Balanced chemical equation:
Complete ionic equation:
Net ionic equation:
c. Pt
Balanced chemical equation:
Complete ionic equation:
Net ionic equation:
d. Ca
Balanced chemical equation:
Complete ionic equation:
Net ionic equation:
 Dr. Gloria Pimienta
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