Name __________________ Foul Water Introduction: One of the major challenges in our society is keeping the relatively small amount of fresh water that we have clean. We use fresh water for a wide variety of activities and many of those pollute the water. We have developed ways to clean this polluted water. Your challenge is to purify a sample of “polluted” water to the point where you could use it to wash your hands. Additional Information: See page 8 in your text for an example of the data table used to record results and hints on how to do the lab. Equipment: Here is a list of possible lab equipment you could use. In your lab book, only include the ones you actually use in the experiment. Make sure to include the amount of each that you use. 100 ml of Foul Water, 100 ml graduated cylinder, 150 ml beaker funnel, ring stand, ring clamp, clay triangle, paper cup, paper clip filter paper, 125 ml Erlenmeyer flask, 150 g decolorizing charcoal sand, gravel, rubber hose Procedure: Use the information on page 8 and 9 in the book as a guide. 1. Develop a data table to record the following observations about your water: color, clarity, odor, presence of oil, presence of solids, and volume. 2. Record the initial amount of foul water and record observations in the data table. 3. Use your observations of the foul water to develop 3 tests (experiments) that will separate the majority of these impurities from the pure water. Remember that your goal is only to make the water usable for washing, not necessarily for drinking. (Hint: charcoal is often used to adsorb (attract and hold on its surface) substances that can give water a bad taste, odor, or cloudy appearance). 4. Write down detailed procedures that you will use to carry out these tests. Make sure someone that is not in this class could use your procedures to replicate exactly your experiment. 5. Conduct the experiments. Make sure to clean and put away all materials when done. Questions: Answer the following questions in your lab notebook. Make sure to include steps used in calculations and complete sentences for other questions. 1. What percent of the original foul water sample was recovered as “pure” water? 2. What volume of liquid was lost during purification? 3. What percent of your foul water sample was lost during purification? 4. What does the conductivity test indicate about the purity of water in your “clean” sample? Discussion Questions: 5. Why do you think distillation is not used by municipal facilities to purify water? 6. What did each step remove? Explain how you know. Use your observations as support. 7. Do you think that this purification process is effective? Why or why not? Think about how much water you recovered, how well the process worked, and long it took, as well as other characteristics that effected how pure your water was or was not. 8. Research question: What ways is water purified in the “real world”? Do some research in your book, on-line, or from other sources to see if our process relates to actual processes or not. Relate the real world to the lab. Look in your textbook, or on the internet (use a search engine and type in “water treatment.”) Try http://ga.water.usgs.gov/edu/wwvisit.html if you get stuck. Rubric for Grading: Point values for each section are listed. Date and Title Hypothesis Materials (10 points) Procedure (15 points) Data Table (10 points) Answers to Questions (25 points) GUM (10 points) Date and Title is missing? Date or Title missing? Date and Title complete No Hypothesis? Hypothesis is there, but needs more thought and detail Hypothesis demonstrates that you put some thought into or did some research before making hypothesis. No Materials? Materials list incomplete Materials list complete Your procedure needs work. It is missing major steps needed for others to repeat the experiment o is very hard to follow. Your procedure is mostly okay. You are probably missing some minor steps needed for others to repeat the experiment. Your procedure is excellent — wellwritten, complete, and easy for anyone else to repeat the experiment. Data table is less than half complete or inaccurate. Your data table is mostly complete and accurate. Your data table is complete and accurate. Answers to conclusion questions are missing or inaccurate. Answers to conclusion questions are mostly complete and accurate and in complete sentences. Answers to conclusion questions are complete and accurate and in complete sentences. May be badly organized, messy, or have many examples of poor grammar, or may have been turned in late. Some disorganization, a bit messy, or a few grammatical errors. Mostly good to excellent in terms of organization, neatness, and GUM.