Quantitative Study of the Reaction between Copper and Silver Nitrate
Chem. 319
Ms. Hobbie
In this laboratory you will use mass/mole conversions and a balanced equation to analyze the following
chemical reaction:
When solid copper is placed into an aqueous solution of silver nitrate, solid silver is
produced in a solution of copper(?) nitrate.
PROCEDURE: DAY 1…
Safety considerations:
 Silver nitrate in solid form or in solution can burn the skin and injure eye tissue. Be sure to wear
safety goggles and avoid getting any silver nitrate on your skin.
 Decant all solutions into the waste container. Nothing should be poured down the sink.
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Coil the copper wire around a thick test tube, as demonstrated, to create spring with an uncoiled
‘handle’. Then measure the mass of your copper wire and record this data.
Mass of copper wire before reaction:_____________________
Write your name on a 150-mL beaker and then measure the mass of the beaker.
Mass of beaker: _____________________
With the beaker still on the electronic balance, tare the beaker and then pour in the white solid
(silver nitrate) from the test tube and record the mass of the silver nitrate added.
Mass of silver nitrate:_____________________
Add between 70-80 mL of deionized water to the silver nitrate in your beaker and stir to dissolve.
Lower the wire coil into the aqueous silver nitrate solution, leaving the non-coiled handle sticking
above the solution.
 Let your beaker sit undisturbed for about 30 minutes.
Observations:
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Gently shake the solid product off the copper coil into the reaction beaker. Use a few squirts of
deionized water as necessary to rinse off any small bits of silver.
 Clean the wire by dipping it into a beaker of deionized water and then in an acetone bath.
 Measure the mass of the copper.
Mass of copper wire after reaction is complete:_____________________
Observations:
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Day2
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Using the method demonstrated, decant most of the liquid solution into a waste beaker.
Rinse your solid by pouring about 10 mL of deionized water down the sides of the beaker and gently
swirling. Decant the rinse.
REPEAT the rinse and decant procedure at least TWO more times.
Place your beaker in a drying oven overnight.
Weigh the beaker with the dried silver AND record any observations.
Mass of beaker and dried silver:_____________________
Observations:
Analysis
1. Write the two balanced chemical equations that are possibilities for the reaction that occurred in
your beaker, including states. (Remember, there are two possible charges on a copper ion.)
2. Use your mass of silver nitrate to determine the mass of copper that should react with it. Do this
twice, once for each of the reactions written above.
3. Use your data to identify the correct equation for this reaction, and thus the charge on the copper
ion produced. Defend your answer in a sentence or two.
4. Is there any evidence that the reaction did not go to completion, that is, that some of the silver
nitrate remained unreacted? Defend your answer in a sentence or two.
5. Using the actual mass of copper that reacted, calculate the mass of solid silver that should have
been produced in the reaction (called the theoretical yield.)
6. Determine the mass of silver actually produced in the reaction (this is called the actual yield).
7. Calculate a percent yield of silver [% yield = (actual yield/theoretical yield) x 100].
Error Discussion (To be TYPED in paragraph form… open to discussion with your classmates)
Consider the many possible sources of scientific error in your experimental method. Some might result in
a yield greater than 100% (positive deviation), while others would result in a yield less than 100%
(negative deviation).
 Identify three possible/likely sources of error.
 Describe how each error would influence your results – would this error make your experimental yield
of silver too high (> 100%, positive deviation), too low (< 100%, negative deviation), or is it a random
error? Explain each answer.
 Identify what you believe is the most significant source of error and defend your choice.
Thought Questions (Also TYPED…these are to be worked on independently, without assistance.)
8. In a few sentences, provide a specific explanation of what is going on at the atomic level in this
reaction. For instance, how are the copper atoms different before and after the reaction, what is
happening to them? Is anything else changing? Is anything not changing?
9. A student comes to the incorrect conclusion about the charge on the copper ion and thus uses the
“wrong” balanced equation in his analysis. Discuss how this would affect both the theoretical yield
and the percent yield that the student calculated. Defend your answer based on theory only – no
calculations.
10. A different chemistry student left the copper wire in the AgNO3(aq) solution for only 8 minutes
instead of longer. She did, however, arrive at the correct conclusion for the charge on the ion and
thus uses the “correct” equation for her analysis. Again using theory only, discuss how this would
affect the theoretical yield and the percent yield of silver the student calculated.
Extension Problems (These are also to be worked on independently… without assistance.)
11. Imagine you had decanted the blue copper (II) nitrate solution into a beaker, and then had
evaporated the water from the solution. The result would be the formation of a solid hydrated
compound, solid copper(II) nitrate trihydrate. What mass of this compound would have been left in
the beaker? Note: base your answer off of the actual mass of copper that reacted (your result from
#5 in the analysis section). Assume 100% yield.
12. What mass of silver would you have produced if there had been enough silver nitrate to react with
the entire copper wire? Again, assume 100 % yield
13. Last week the price of silver was reported to be $21.98 per ounce. What is the dollar value of the
silver you collected in the lab? (Yikes! Last year it was $34.32 per ounce… what is going to happen
to my retirement savings?)
Your Report
 Data table: Raw data only.
 Analysis with supporting explanations, as necessary. Make this a NARRATIVE, not simply a numbered
list of the answers to the above directions.
 Error discussion paragraph(s).
 Thought and Extension questions – simply answer the questions and attach to the report