Reactivity of Metals
Laboratory
Purpose
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To measure the relative reactivities of selected metallic elements.
Background
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Elements have different uses depending on their reactivity.
Gold is commonly used in jewelry because it is so resistant to chemical reactions.
Sodium is not used in jewelry because it explodes when it contacts water.
Differences in chemical reactivity depends on the relative ease with which elements give up electrons.
You can measure relative reactivity of two metals by placing a sample of one metal in a solution of the ions
of the other metal.
If the solid metal sample is more reactive, electrons will move from the metal into the solution and the solid
sample with become ions and dissolve.
Meanwhile, the less reactive ion sample will take the electrons and form a solid.
This is an example of a redox reaction because electrons are transferred from one species to another.
If the solid sample is less reactive than the ionized metal solution, no reaction will occur.
Your Mission
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To test the reactivities of a variety of metals with different metal ions.
To write chemical equations for each reaction that occurs.
To then use the results of your tests to construct a scale of relative reactivities of the metals.
To write electron configurations for each metal and attempt to explain relative reactivity based on electron
configuration.
Materials needed per pair
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Goggles and aprons; gloves are recommended
Well plate
Dropper pipets
Forceps
Steel wool or sand paper (to polish any corroded solid metal samples)
Chemicals supplied
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Copper wire or mesh
Zinc foil
Magnesium ribbon
2.5% lead(II) nitrate solution
2.5% copper(II) nitrate solution
0.1M silver nitrate
2.5% magnesium nitrate solution
Caution!
• Be familiar with the hazards associated with chemicals before handling them!
• Read bottles, refer to MSDS information, ask questions.
Procedure
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Labs need to be written in the 3rd person, singular, present tense, neutral gender.
Instead of “add 5 drops of copper nitrate solution” write “5 drops of copper nitrate solution is added”
Instead of “we added the magnesium to the test tube” write “magnesium is added to the test tube”
These are the metals you will be testing:
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Lead, copper, zinc, magnesium
Write a procedure to compare these metals, using the chemicals that are provided, so that you will have the
data you need to put the metals in order of increasing reactivity.
Plan this before you begin working in the lab.
Data and Observations
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Construct a table to record data and observations.
Here is a suggestion:
Tube
Metal ion
Metal
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Pb2+
Cu
Observations
Calculations
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Write unbalanced net ionic equations for the redox reactions that actually occur.
– Ex. Na + Mg2+  Na+ + Mg
Write Noble gas notation (electron configurations) for the metals (Cu, Mg, Pb, Zn) and their ions
You will need to do some reasoning to put your elements in order. Do this work in the calculations section.
Show your thinking.
Conclusions
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This should be statements that compare the reactivities of each of the elements citing laboratory data as
evidence to support each conclusion.
– Ex. Sodium is more reactive than Magnesium. When solid sodium and magnesium ion were
combined a reaction occurred, as indicated by bubbling and heat.
Error Analysis
• Specific sources of error are be discussed.
• There is no precision or accuracy to calculate.
Discussion
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Connect your lab observations to the atomic structure, specifically referring to electron configurations. Do
at least 2 examples like this:
– Ex. Sodium ([Ne]3s1) has only one electron in its outermost shell to lose to become stable while
magnesium has two valence electrons. This explains why sodium reacts more vigorously to lose its
electron when compared to magnesium.
Describe what you think would happen if strips of lead were put into sodium chloride solution. Describe
what you think would happen if strips of lead were put into copper nitrate solution. Explain why using both
lab data and the concept of reactivity.
For a “4” in this section, connect these observations to the electrochemistry concepts and the measured
voltages between dissimilar metals (electromotive series table).