Fish Kill Formal Lab Report
Devin Dustman
Katie Nolan
Lab Section #201
11/8/2016
Introduction
A “fish kill” is an event in a body of water in which a large number of the fish population
in an area die off. In 1984, a fish kill occurred in the Clark Fork Columbia River in Montana.
The fish kill has been attributed to toxic levels of Group IA and IIA ions in the water, which
make the water too salty for freshwater fish. The purpose of this experiment is to determine what
caused the massive fish kill in the Clark Fork River by analyzing the presence of Na+, K+, Li+,
Ca2+ , Ba2+, Sr2+, Cu2+ and Fe3+.This report will include whether toxic levels of Cu2+ and Fe3+ are
in the water.
The process for this lab involves using two different procedures introduced in previous
lab experiments 10 and 11. Experiment 10 involved using a flame test and a spectrophotometer
to determine which ions were present in an unknown sample. The second part of this experiment
is to determine what the concentration of Cu2+ and Fe3+ is in the river water sample. This uses
procedures in experiment 11, which involved using absorbance spectroscopy to determine the
concentration of copper sulfate in an unknown sample. By recording absorbances of solutions
with differing concentrations of each of the ions, and using Beer-Lambert’s Law, it is possible to
determine what the concentration of Cu2+ and Fe3+ in the lake water is.
This experiment will give us a better idea about what threats are endangering the fish
population in the Columbia river. Knowledge of this threat could help us better avoid similar
issues in the future, as well as being able to address the possible crisis.
The MeasureNet spectrophotometer will be used in both parts of the experiment for
emission and absorption spectroscopy. It will involve the process of burning standard 0.5 M
solutions of Na+, K+, Li+, Ca2+ , Ba2+ and Sr2+ and recording the emission spectra with the
MeasureNet. The graphs the data of the wavelengths given off by the known solutions will be
compared to that which was given off by the river water. This can be used to determine which
ions are present in the water.
Then, in order to determine whether there are toxic levels of Cu2+ and Fe3+ in the river,
the MeasureNet will be used to gather data about the absorbances of five solutions of [CuSCN]+
and [FeSCN]2+ with differing concentration, beginning with a solution of 400 ppm for each and
diluting it by using the equation M1V1=M2V2, where M is the concentration and V is the volume.
The absorption spectra of the known solutions will be graphed along with the absorption spectra
of the unknown river water in excel, and a Beer-Lambert plot will be used to determine a linear
regression that will allow the concentration of the ions in the river to be found.
Experimental
A. .5 M NaCl solution
B. .5 M LiCl solution
C. .5M KCl solution
D. .5M CaCl2 solution
E. .5M BaCl2 solution
F. .5 M SrCl2 solution
G. Fe/Cu solution made up of 400 ppm Cu2 and 400 ppm Fe3+in a solution of SCN-
H. .1 M iron(III) nitrate solution, has SCN- mixed in already
I. .1 M copper (II) nitrate solution, has SCN- mixed in already
J. Simulate Clark Fork of the Columbia River Water Sample
Procedures
The first step is to prepare the MeasureNet station by first turning on the machine. After
this is done, begin by acquiring .5 molar solutions of NaCl, LiCl, KCl, CaCl2, BaCl2, SrCl2. Once
these solutions are collected the spectrophotometer must be prepared to take the sample.
Next, set the bunsen burner up in the correct fashion, at a height that the inner portion of
the flame will line up well with the detection wire, a.nd create a flame or reasonable size and
shape Once the flame is burning, transfer a portion of the solution into the gas intake of the
bunsen burner. This is done by transferring a small portion of the solution into a watch glass,
heating a cleaned nichrome over the bunsen burner until is is glowing orange, and pressing the
wire into the watch glass, spattering the solution into the intake valve. As soon as this solution
enters the bunsen burner, and the fire begins to change color, record the wavelength of the flame
using the emission spectrophotometer, by quickly hitting the Sample button. The information
recorded will be transferred back to the MeasureNet station which must than be saved before
gathering further data.
To complete the next part of the experiment, the MeasureNet station needs to be set up
once again, this time for absorbance spectroscopy. After the MeasureNet is setup properly, the
three samples of CuSCN+, FeSCN2+, and a solution of the two ions combined must be collected.
These first must be broken up into 5 solutions of differing concentrations. These need to be 400,
320, 240, 160 and 80ppm for the iron and split up into likewise increments for the copper and
combined solutions. To do this, first fill a cuvette three quarters full with the undiluted 400 ppm
solution of either the copper or iron. Then, measure out 8.0 mL of the solution and transfer it to
a volumetric flask. Then fill the flask to the 10.0 mL line with distilled water. Transfer this
solution to a cuvette and fill it about three quarters full. Repeat this procedure with the rest of the
400 ppm solution, measuring 6.0 mL, 4.0 mL and then 2.0 mL, and use distilled water to fill the
flask to the the 10.0 mL fill line to create the rest of the solutions. After, fill a cuvette with each
solution three quarters full. Do this for the other five samples. Once the solutions are in the
cuvettes, their emissions must be tested using the MeasureNet. Once these five have been
completed, repeat the procedure for the copper, combined, and unknown solutions.
Results
Solution 𝝀 at Two Highest Intensities
Water Sample
NaCl
LiCl
KCl
CaCl2
BaCl2
SrCl2
What ions are present in the water sample?
___________________________________________________________
Concentration of CuSCN+ (ppm) Absorbance at 𝝀 max:
Water Sample
400
320
240
160
80
Line of Best Fit:
Concentration of Cu Calculation:
Concentration:___________________
Concentration of FeSCN2+ (ppm) Absorbance at 𝝀 max:
Water Sample
20
16
12
Line of Best Fit:
Concentration of Fe Calculation
Concentration:___________________
Concentration of CuSCN+ Absorbance at 𝝀 max:
(ppm) and FeSCN2+ (ppm)
Water Sample
420
336
252
168
84
Lines of Best Fit:
Concentration calculation:
Discussion
Our results are very much mimicking a real life scenario where large numbers of
contaminants enter water systems and scientists are required to test said water for possibly
dangerous contaminants, and despite better testing alternatives in practice, this is still a valid
route to detecting pollutants. Once we know what kind of contaminants, and their presence in the
water, we can try to eliminate the chemicals, or possibly just raise awareness about the threat
they posed. Our data shows, if accurate that a massive number of fish will likely die, with levels
far higher than what any normal fish can survive.
Possible Errors
One of the main errors that comes with the territory of doing quick labs is that we only
really have time to one test on a particular sample, and if we wanted more accurate results we
could have done the same tests multiple times. As well as this, there may have been some issues
with our quick transfer between cuvettes, as sometimes, we did not properly clean off the cap as
thoroughly as we should have. This is because it may have continued a small amount of our
earlier used solution into the cuvette containing a different solution, which may have once again
slightly altered the results. This issue could have been fixed by us simply using more caps on the
cuvvts, which would have totally eliminated this issue. As well as this we had some slight issues
with quickly measuring out the solutions, as we were on a heavy time constraint, and the results
would in all likelihood be more accurate if we were to instead take a little more time and use a
slightly more accurate measurement device. Finally some of the data we used was from previous
experiments, which is of course unideal, and the data could have been made more retesting all
earlier data on the spot.
Conclusion
For this experiment we detected what the sample of liquid was, by comparing it to the
other metal ions we detected in an earlier experiment. From this we discovered that the unknown
contains particles of ___ ___ ___. Once we had the makeup of the solution we had to find the
concentration, and we did this by making a beer lambert plot of the unknown, and a lambert plot
of Copper and Iron. We used these beer lambert plots to find the ppm of the unknown by first
imputing some number into the plot for the unknown, and putting this given number into the beer
lambert plot for both the Copper and Iron beer lambert plots, and this will give us the maximum
containment value for both copper and iron. We discovered that the amount of copper in the
water is 405 ppm, and Iron is 9.86 ppm. This concentration indicates that the fish population of
the river will be crippled if not entirely destroyed. As the EPA stated that, fish cannot survive
concentrations of iron over .3 ppm of Iron, and 1.0 ppm of copper, and of course our numbers are
far higher, indicating a massive loss of fish.
Bibliography
Stanton, B., Zhu, L., & Atwood, C. H. (2006). Experiments in general chemistry featuring
McomparieasureNet. Belmont, CA: Thomson Brooks/Cole.
Drinking Water Contaminants – Standards and Regulations. (n.d.). Retrieved November 09,
2016, from https://www.epa.gov/dwstandardsregulations
Chemical Listing and Documentation of Revised IDLH Values (as of 3/1/95). (2014). Retrieved
November 09, 2016, from http://www.cdc.gov/niosh/idlh/intridl4.html
CAUSES AND EFFECTS OF POLLUTION ON FISH. (n.d.). Retrieved November 09, 2016,
from http://www.fao.org/docrep/009/t1623e/T1623E03.htm
