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Unit 1Foul1 Foul Water Activity – Report Guidelines
Julia Tolmachyov, Francesca Cali, Galen O’Neill
1) Introduction
• Our group goal throughoutThroughout this lab islab, the ultimate goal was to completely dirt, bacteria, and harmful substances desert island.
• Undoubtedly,
Undoubtedly, there arewere many substances Most likely, thisthe water iswas filled with algae, etc. Oil and solid materials were also detected in the water. Again, our said impurities.
• Based on hypothesis, we planplanned to purify resources. This includesincluded filter papers, fire. We planplanned to filter possible particles. We plan on adding charcoal to the filtered water to make it clearer. This remaining substancessample will be harmful bacteria.
Hypothesis: The foul water can be purified by pouring the water through filter papers and a Styrofoam cup filled with sand and gravel, and the end result will be boiled to remove all solids and impurities
2) Procedure/Data/Observations
In order to purifyFor the first trial of this foul water, each resource is vital. One ourexperiment, it was decided to first daydrain a sample of lab, September 19, 2011, we began our first trialthe contaminated water to purifyremove any visible sediment. First, the water. First, we took our Styrofoam cup was taken and transferred its contents--gravel and sand--intosand--were transferred into a small to hold. We punched three smallThree holes were punched in the cup, which will later be drainingwas used to drain the water. Next, we took a piece filter paper andwas placed it at the filtering through this cupthe Styrofoam would eventually paper. Since we havethere was unlimited gravel and sand, we filled the cup was filled about ¼ of the way up with sand. This will furthersand, in order to help drain water. Because wethere was only have a limited amount of charcoal, this resource willwas not bebeing used until it iswas certain that this filtration method iswas successful. We used a ringstand and anAn iron ring attached to a ring stand was used to hold place over ourthe Styrofoam cup, which itself iswas nestled in a beaker which willin order to catch the filtered water. InAnother filter paper was placed in the glass funnel, we placed another filter paper. We directly pouredfunnel. 50 millilitres foul water was poured into this The water takestook a very long time to drain completely, so weit was left this water to drain the day. Tomorrow morning, we will see if our system of purifying the foul water was successful. If not, we will plan another method.
On
On day two of lab, we observed and tried several new purify the water.water were tried and observed. At 8:00 a.m., our group returned toit was found that the trial Styrofoam cup filter--and found that the filter paper and the cup’s contents helpedfilter--helped remove all in the solution.mixture. This iswas a problem not only iswas the water important resources. OurThe first trial day two was to attemptattempted to separate the bottle’s water and the unwanted oil.oil in the filtered sample. Since oil heterogeneous mixture, we attempted to separate the two substances bysolution was slowly pouring the oilpoured out of the bottle, leavingbeaker in an attempt to separate the oil and water. If this mixture had been homogeneous, the water and oil would not have been distinguishable in the bottle.mixture. This trial was unsuccessful or position we poured the solution out,was poured, the oil on the top. Thistop, as oil has a density less than water and will always float on the surface. Even though this trial was unsuccessful, however, we did not lose or waste anyno resources by trying this. In ourwere wasted or lost.
In the third trial, we attempted to purify the water by filtering 110 millilitres of a new sample of water was filtered through a a glass funnel. We added morefunnel in the hopes of removing all solids. More gravel and sand--filledsand was added to the previously filled Styrofoam cup about ¼ more--inin an attempt from the water.water and remove all visible impurities. This trial was also unsuccessful because solids present. Tomorrow, we will do the same experiment, except we will also useIt was inferred that this result was achieved because there had not been filter paper atplaced on the bottom of the Styrofoam cup to separateat the final solids that may come through the holesstart of the cup.
Dayexperiment, as there had been in the first trial.
Day three of day for ourthe lab group. Again, in ourthe fourth trial, we attempted to filter the oily water was filtered through the Styrofoam cup. WeIt was decided to dothat a larger for this method.method was needed. More gravel the base. WeA greater volume of water was also used more foul water in thisfor the test. Through the cup, we poured 125 mL dirty, oily water.water was poured. This process minimal sediment. We realized that to decrease the level of oil in the water further, we could pour as much oil as possible out of the bottle first, then filter the rest through the Styrofoam cup to almost completely eliminate any oil present in the water. This
This resulting water murkiness, so weit was filtered this water with another in a funnel.funnel in our next trial. To this funnel, we added a small of charcoal was added to see its effect ofon the water. This filtering plusdecreased the small amountvolume of charcoal madewater from 77mL to 75mL, but the resulting 75 mL water was considerably clearer. Now, with oil-free water, our team can focus on filtering the rest of the water and adding charcoal.
*integrate the slide terms into these paragraphs; accuracy, precision, mixtures, etc*
Onclearer than before.
On day four our lab, wethere was only had about twenty20 minutes to work with our trials.the trial. During this time, continued to add charcoal was added to the sample in an 8:26 a.m., we filtered 75 mL the yellowish water. Wewater was filtered. This sample was poured this through a the yellowish tint,tint - but some blackish tint. ThisIt was planned to filter the charcoal out of the water will be filtered further tomorrowthe next day when we havethere was more time for lab. We plan on usingexperimentation. It was also proposed to start a more full-scale model of ourthe method.
• Data – volumes before
On day five, a new trial began. 142 mL of the foul water was filtered through the Styrofoam cup with a filter paper, gravel, and sand (from bottom to top). This process took 80 seconds and resulted in 90 mL of almost complete oil and sediment free water, though murky and not clear. We filtered this through another filter paper and funnel which took 9 minutes and 40 seconds. 80 mL resulted after each stepthis filtering and is clearer than before. After this, 4.9 mL of your purification
• Observationscharcoal was added directly into the water and swirled this in a beaker for 30 seconds. Again, the charcoal and water mixture was filtered through a filter paper to remove the charcoal and came out with 22 mL of your initialconsiderably clearer and final samplescleaner water.
However, the resulting substance was not a pure compound of the elements hydrogen and oxygen (water). The result after filtration was a homogeneous mixture in which the salt in the water as well as ofcould not be physically observed, but was clearly present because one could taste it in the sample. On day seven, a distillation apparatus was used to finish the purifying process and completely remove any intermediate
products (what you keepbacteria, salt, or sediment from the solution, in other words to derive the pure substance (compound) of water from this mixture. This apparatus included a ring stand and what you remove)
• Sample chart:a utility clamp to hold a Florence flask. The water was held in the flask and brought to a boil by the Bunsen burner beneath it. The steam from the boiling water was condensed and collected in a graduated cylinder, leaving the impurities behind. This process removed all of the salt that was still present in the water. The trial began with 22mL of water and resulted in a 15 mL after the distillation. The distillation took 120 seconds to be completed (the distillation is completed when the water droplets fall less frequently than they previously had) and left behind a large amount of salt. Only now was this substance truly pure water.
Overall, the experiment was precise because all of the times, observations, and steps were recorded. As a result, this experiment is reproducible.
Trial 1:
Procedure
Approx.
Time
Initial
volume volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
beforeafter procedure
Filtering a new water sample through funnel with filter paper into Styrofoam cup with gravel and filter paper
Overnight
50mL
Water is murky, filled with small particles, oil, yellow in color and has a strong odor
28mL
All solids are removed from water, which is still murky in color, has an odor and oil
Trial 2:
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Slowly pouring the 37 mL of water from Trial 1 into a beaker to try and remove the oil on top
10 seconds
37mL
Water is murky and has a plethora of oil circles floating on top
37mL
Water in beaker is identical to the initial sample
Trial 3:
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Filtering a new water sample through funnel with filter paper into Styrofoam cup filled with gravel
3min 27 sec
110 mL
Water is murky, filled with small particles, oil, yellow in color and has a strong odor
93mL
Large particles are removed, but water is still very murky in appearance with sediment floating throughout
Trial 4:
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Filtering a new water sample through funnel with filter paper into Styrofoam cup filled with gravel and filter paper
4 min 53 sec
125mL
Water is murky, filled with small particles, oil, yellow in color and has a strong odor
77mL
Water is mostly oil-free and contains minimum sediment, yet is still murky in appearance
Trial 5:
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Filtering the resulting 77mL of water from Trial 4 through a funnel with filter paper and a few pinches of charcoal
7min 10 sec
77mL
Water is mostly oil-free and contains minimum sediment, yet is still murky in appearance
75mL
Water is considerably clearer but retains its yellow tint. The sample is basically oil-free and odorless.
Trial 6:
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Filtering the resulting 75mL of water from Trial 5 through a funnel with filter paper with about twice the charcoal used in Trial 5
8min 6 sec
75mL
Water is considerably clearer but retains its yellow tint. The sample is basically oil-free and odorless.
70mL
Water has lost its yellow tint – due to charcoal falling through the funnel though, it has a black tint.
Trial 7:
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Filtering a new sample of water through a Styrofoam cup with filter paper, gravel, and sand
80 seconds
142mL
Water is murky, filled with small particles, oil, yellow in color and has a strong odor
90mL
Water is almost completely oil and sediment free, although murky
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Filtering the resulting 90mL from Step 1 through a funnel and filter paper
9 minutes 40 seconds
90mL
Water is almost completely oil and sediment free, although murky
80mL
Water is considerably clearer than before, but still opaque
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Adding 4.9 mg of charcoal to the 80mL of water resulting from Step 2 and swirling the beaker
30 seconds
80mL
Water is considerably clearer than before, but still opaque
80mL
Water has a black tint as it is filled with particles of charcoal
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final volume
(mL)
Observations
after procedure
Filtering the 80mL of water and charcoal through a funnel with filter paper
7 min 5 sec
80mL
Water has a black tint as it is filled with particles of charcoal
22mL
Water is clear, oil-free, and odorless
Procedure
Approx.
Time
Initial volume
(mL)
Observations before procedure
Final
volume volume
(mL)
Observations
after procedure
3) Calculations
• PercentBoiling 22mL of water and collecting the condensation droplets
120sec
22mL
Water is relatively clear, yet is still not fully transparent
15mL
Water is 100% pure clear, oil-free, and odorless
3.)Calculations:
To calculate if this process will produce enough water for the 3 survivors to survive each day, first it was researched how much water was needed for an average women to survive. The result was 8 cups, or about 1,893mL. For three people, this comes to 5,678mL per day to be filtered.
The percent yield of this experiment was found by calculating the final volume of pure water divided by the beginning volume of foul water and then multiplied by 100. The beginning volume of foul water in our last trial was 142 mL and after several steps of filtration, the final volume of clear water was 22 mL before distillation.
It is known that out of 73mL of water, 50mL was left after the class distillation. To find the percentage of distillation, the equation
50mL (resulting volume) / 73mL (starting volume) = (beginningabout .68
.68 x 100 = 68%
is performed. This equation shows that overall, the results of the distillation process are about 68% of the starting volume. Using this model, the volume of our resulting water sample can be calculated.
22mL (starting volume of distillation) / .68 (percentage left) = about 15mL
Thus, the final volume of clear water after distillation is 15 mL.
To calculate the total yield of the experiment, the equation
15mL (resulting volume) / 142mL (starting volume) = about .105
.105 x 100
• Where appropriate, show how much = 10.5%
is performed. Thus, after extensive experimentation, the total yield of an impuritypurified water was removed
4) Discussion
• Explain%10.5 of what your goalthe group started with.
Before the start of experimentation, it was forcalculated that each step (What did you hopesurvivor on the island would need 8 cups, or 1,893mL in order to remove fromsurvive each day. As this would only be the water?)
and discuss its success/failurefinal result, the proportion can be set so that 5,678mL is %10.5 of the starting water sample.
10.5 / 100 = 5,678 / x
Following this math, the starting water sample would need to be about 54,076mL. As it took the group a total combined time of 20min 35sec to purify 142mL of water, a proportion would show that it would take the group a total of 5 days, 10 hours, 38 min and 28 seconds to purify 54,076mL.
1235seconds/142mL = x seconds / 54,076
Thus, it can be seen that using the methods performed in the laboratory, the survivors would not be able to filter water at a sufficient rate (54,076 mL per day) to survive the island.
4.)Discussion:
The overall goal of the lab was to purify the water. All members of the group contributed to constructing a hypothesis based on yourthe given information before the experiments began. As the trials occurred, changes to the hypothesis were made. Error and results
• Describe of the trials also influenced the decisions made by the group to alter parts of the experiment to make it successful. The original hypothesis states: The foul water can be purified by removing solids and explain/justify any procedural changesoil from your introduction (Did you
change/skip/add any procedures? Why? Are you satisfied thatthe solution by pouring the water through filter papers and a Styrofoam cup filled with sand and gravel, and the end result will be boiled. In this original hypothesis, it was the right thingplanned to
do? Why or why not?)
• Identifyremove the oil and solids through the Styrofoam and the rest of the impurities your(salt, bacteria, dead organisms) through boiling. This hypothesis changed throughout the experiment.
The goal of Trial 1 was to remove large particles of sediment and the oil from the foul water through the Styrofoam cup and filter papers. This was successful--almost all of the sediment/solids were removed but their was still some oil present in this heterogeneous mixture. To remove the remaining oil, the group decided to separate the oil from the water by pouring the oil off the top of the bottle - Trial 2. This proved unsuccessful because oil’s density is less than water’s density, and justify your conclusions, taking
into account your original hypotheses
• Analyzeas a result this pure substance will always float on top of water. After this failure, the sourceslab group decided to go back to the first method tested, thinking that if a small amount of rocks removed some of the oil, a larger amount would probably remove a larger amount of oil. In Trial 3, the goal was to separate the oil from the water, as well as the solids present in the new sample. This trial was successful in removing most of the oil from the mixture, but many solids remained as the group failed to repeat the first Trial exactly - there were no filter papers on the bottom of the cup. Thus, the goal of Trial 4 was to redo Trial 3, except adding a few additional filter papers to the bottom of the Styrofoam cup and the glass funnel to ensure that all sediment was removed. This was successful because the solids are removed by the filter papers, and most oil by the rocks, but the water still had a murky appearance. In Trial 5, the group took the result of Trial 4 and added a small amount of charcoal. The goal of this was to remove the water’s murky appearance and make it fully transparent. The result was considerably clearer water, but it still had a yellowish tint to it. In Trial 6, the results of the previous trial was filtered through a filter paper containing more charcoal. The goal was to remove the yellow tint and make the water completely clear. This was successful in that the yellowish tint was removed, but the water then had a blackish tint because some of the charcoal had unexpectedly fallen through the filter paper into the water. From here, the group looked at their observations. Trial 7 was a full scale trial based on all of the revisions made to the experiments by the group members. All previous errors and mistakes were taken into consideration while making this trial. The goal of Trial 7 was to remove all oil, solids, and murkiness from the new sample. First, the water was filtered through the Styrofoam cup filled with filter papers, rocks and gravel to remove all visible solids (organic material) as well as oil. Next, the water was filtered through a single filter paper to remove smaller sediment. The remaining sample was then mixed with charcoal, as this procedure had proved to clear the water previously. The new charcoal/water substance was then filtered to remove the charcoal, resulting in visibly clear water. Finally, this water was boiled to remove any salt and bacteria present. In this final trial, the group used observations and techniques gathered from all previous trials to perform a full-scale water filtration and distillation.
The hypothesis was revised many times during the experiment as error occurred and as changes needed to be made in your procedures. Explain why yourorder to successfully purify the water. For example, in the beginning, the group was not sure about how the charcoal could be used. By learning from their classmates’ trials, it was realized that the charcoal could be used to purify the water and make it clearer. This change to the experiment was made. Also, the group realized that their clear water could not be just boiled, but an apparatus was needed to collect the condensation of the boil. Without this, only the leftover salt and sediment would remain and the water would evaporate into the atmosphere. It was an important realization. Through personal knowledge and learning from classmates’ photos on the Wikispace, the appropriate changes were made to the hypothesis to make the successful.
Error was also a factor taken into consideration. Error could have occurred throughout these trials due to incorrect measurements. Although all measuring of liquid substances was done in graduated cylinders, room for error must be left. It is hoped that our experiment was precise as all of the data and measurements were recorded so the procedure would be able to be reproduced. As there are no known measurements to compare the results to, we can not be sure of their accuracy, but it is hoped that future tests will produce close results to prove these conclusions accurate.
In conclusion, the yield is not and
shouldshould not be to be 100%.100% as much water was lost in the filtration process when it was stopped by sand, gravel, charcoal, etc. Also, much of the starting volume consisted of oil and solids, which were extracted before the ending sample was measured. In addition, since the experiment was not performed all in one day, some water could have evaporated overnight and could have tampered with the accuracy of the results.
5) Conclusion
• AnalyzeOverall, the level of success yourlab group had in purifying yourwas successfully able to purify the foul water sample based on
observationssample. The results of your final productthe filtration and any tests you performed
• Describe any changes you would make now to yourdistillation procedures left the pure compound, water, in place of the heterogeneous mixture that was its processor. Some of the trials performed, such as the filtration in the Styrofoam cup, the mixing with charcoal, and the benefitdistillation proved incredibly effective in removing dirt, oil, bacteria and salt from the sample. Other trials, such as the pouring of
hindsight or any other procedures you would have performed butthe sample to remove the oil, did not think of soon
enough
• Discuss your overall experienceprove as effective. Looking back, another trial is believed to may have been beneficial - a medicine dropper could have been taken to suck up and remove the oil floating on top of the foul water. Yet, the lab group is content with the procedures and believes that the experiment was performed in performingthe most efficient way possible, as little resources were wasted and all of the trials gave important insight and aided in drawing conclusions. Throughout this activityprocess, all members of the lab group worked well together, sharing roles and working to reach the goal of purified water. All members of the team worked quickly and contributed to the ideas for experiments and solutions. All in all, the foul water lab was an equal effort by all team members, and the successful results of the experiment directly correlate to the hard work put in by each participant.

So the minimum amount of water to replace what has been lost and thus not become dehydrated in a very hot climate with activity is 8 cups which is two quarts and 1.8927 liters
There is enough water for 8 people for 14 days:
8 cups 8 people 14 days = 896 cups or 211.983 Leters{eq1.JPG}
However, the group on the boat took three quarters of the water:
896 cups4 =224 cups or 52.9957 Liters{eq2.JPG}
So the three of us on the island have 224 cups/ about 53 Leters of water
224 cups8 cups =28 cups{eq3.JPG} this means 28 days. 283 = 9.3
{eq4.JPG}
There is enough water to last our group 9 and one third days

This is the scenario that our PBL was based on:
Background to PBL 1
You were a passenger on an aircraft that has crash landed on a deserted island in the south
Pacific Ocean. Only eight (8) of you have survived. The average temperature in the shade on
the island is 90 defrees farenheight.
You have scoured the wreckage of the plane and found that there appears to be no food and only
water for eight (8) persons for 14 days. However, you did find two (2) inflatable dinghies with
small sails but one boat can only safely fit four (4) people.
Strangely, you find a chemistry set in a recovered suitcase.
These were the materials found in the chemistry set.
Careful analysis of the chemistry set shows the following laboratory equipment:
1 - 100 mL graduated cylinder
1 - 150 mL beaker
1 glass funnel
1 ring stand
1 iron ring
1 clay triangle
1 pinch clamp
1 styrofoam cup
500 filter papers
1 - 150 mL Erlenmeyer flask
500 g of fishtank gravel
2 ft of rubber tubing
In addition, you have the following items at your disposal on the island:
unlimited sand from the beach
2 Kg charcoal ash (leftover from your campfire)
fire and plenty of wood
Reconnaissance of the small island has determined that there is no fresh drinking water supply. Rather, there appears to be a swampy, foul-smelling pool of water near the middle of the
island. A meeting of the survivors shows a clear distinction between those that believe the only chance
for survival is to leave immediately on the dinghies with the limited water left and others who
believe that they can purify the foul water using the chemistry equipment recovered. A
compromise is reached and it is decided that four (4) people will attempt rescue by leaving the
island on one of the dinghies. However, they will be taking three quarters (3/4) of the water left
on their journey.
Your group of four (4) will stay behind and await rescue. There is no time to waste. You have
very little water and less time to figure out how to purify the water from the foul pool.
Will you survive?

{FOUL_WATER_TITLE.jpg}{homepage.JPG}