DIRECTIONS Conduct a three-part experiment to simulate the effects of ocean acidification on coral reef marine life (i.e. destruction of the coral reef calcium carbonate structure). This multi-day experiment will occur over a five day period. PROBLEM STATEMENT(S) A. Experiment # 1: What effect does one day exposure of acetic acid (vinegar) have on the calcium carbonate found in egg shells and sea shells? B. Experiment # 2: What effect does prolonged exposure of 1 day, 3 Days, and 5 Days of acetic acid (vinegar) have on the sea shell (or calcium carbonate exoskeleton) of marine animals? C. Experiment # 3: What effect does five days of exposure to acetic acid (vinegar) have on organic molecules found on the inside a raw egg shell (or calcium carbonate structure)? MATERIALS (PER GROUP) 1.5 Quarts of Distilled White Vinegar () 3 Sea Shells 2 Egg Shells 2 Raw Eggs 3 Cup (To Serve as Containers) 3 Labels (Stick-on) Marker Small Paper Plate Paper Towels 1. Use the Vocabulary handout (internal link) to assist with group discussions and answering questions. 2. Label three (3) containers with the following: Container 1: 1 Day Observation of Sea Shell and Egg Shell In (Vinegar) Container 2: 1, 3, and 5 Day Observations of Sea Shell In (Vinegar) Container 3: 5 Day Observation of Raw Egg In (Vinegar) 3. Record your observations of the sea shells, egg shell, and raw egg before beginning the experiment in your science notebook. You will observe the surface and test how easy it is to break or tear off a piece of each of the shells. Also, you will devise a method(s) to test one of your raw eggs. Refer to each experiment section and write all initial observations in each of the charts. 4. You will conduct three experiments to simulate the destruction that acidification of the ocean cause to marine life. PG. 1
5. Experiment # 1: What effect does one day exposure of acetic acid (vinegar) have on the calcium carbonate found in egg shells and sea shells? A. Place the labeled Container 1: 1 Day Observation of Sea Shell and Egg Shell in (Vinegar) in the center of your group. B. Record the observations in your science notebooks of what happens when eggshells are placed in acetic acid (vinegar). Be sure to write all your responses in complete sentences. C. Also, record in your science notebooks what happens when sea shells are placed in acetic acid (vinegar). Write all your responses in complete sentences. D. If you observe any bubbles (gases) be sure to record them, as well as any color or temperature changes and E. Allow the egg shell and the sea shell to sit in the acetic acid (vinegar) for one full day. F. Upon your return the next day, drain both shells from the mixture and rinse them off with water. Determine the strength of each shell by comparing your initial observation made to those of the shells today. G. In your science notebook, record all observations in the chart format below. Egg Shells Initial Observations Before One Day Observation In Comparison Sea Shells PG. 2
6. Experiment # 2: What effect does prolonged exposure of 1 Day, 3 Days, and 5 Days of acetic acid have on the sea shell (or calcium carbonate exoskeleton) of marine animals? A. Place the labeled Container 2: 1, 3, and 5 Day Observations of Sea Shells in (Vinegar) in the center of your group. B. Record the observations in your science notebooks of what happens when sea shells are placed in acetic acid (vinegar). Be sure to write all your responses in complete sentences. C. If you observe any bubbles (gases) be sure to record them, as well as any color or temperature changes and D. Allow the sea shell to sit in the acetic acid (vinegar) for one full day before making an observation, then allow it to sit for an additional two days (totaling three (3) days) before making an observation, and finally to sit for an additional two days (totaling five (5) days) before making the final observation. E. Upon your return each time, drain the sea shell from the mixture and rinse it off with water. Determine the strength of the sea shell by comparing the initial observation made to those of the shell on day five observation. F. In your science notebook, record all observations using the chart format below; comparing the observations seen initially, and after one day, three days, and five days in acetic acid. Initial Observation Shells Before One Day With Observation of Seashells Comparison of Before and After Shells Were Added to the Acetic Acid SAME Three Days With Five Days With PG. 3
7. Experiment # 3: What effect does five days of exposure to acetic acid (vinegar) have on organic molecules found on the inside of a raw egg shell (or calcium carbonate structure)? A. Place the labeled Container 3: 5 Day Observation of Raw Egg In (Vinegar) in the center of your group. B. Record all initial observations using only one of the eggs. Observe and record observations of the outside of the whole raw egg, and then crack it open and record the observations of its inside organic materials. Please note the inside egg (organic materials) colors, consistency, surface texture, etc., as well as the hard egg shell it came from. C. Record the observations in your science notebooks of what happens when the second whole raw egg is placed in the acetic acid (vinegar). Be sure to write all your responses in complete sentences. D. If you observe any bubbles (gases) be sure to record them, as well as any color or temperature changes and E. Allow the whole raw egg to sit in the acetic acid (vinegar) for five days undisturbed. F. Upon your return after five days, drain the egg from the mixture and rinse off the vinegar from it. Determine the strength of the egg by comparing your initial observation made to those of the egg today. Open the egg and observe and record the inside of the egg. Compare the initial observation recorded to the observation of today. G. In your science notebook, record all observations in the chart format below; comparing the observations seen initially and after five days in acetic acid. Egg # 1: Outside of the Whole Raw Egg Initial Observations Before Day Five Final Observation After (Whole Egg Closed and Opened Egg) No Observations Are Required Egg # 1 Cracked Opened Whole Raw Egg (Inside) Egg # 2: Whole Raw Egg No Observations Are Required PG. 4
COMPREHENSION QUESTIONS Complete the following Comprehension Questions and be prepared for your group to answer these questions during your class presentation. In what way is the egg shell like the coral exoskeleton, and in what way is the raw egg materials (organic molecules) representing the marine organisms found in coral? List as many sea creatures as you can think of that have calcium carbonate shells or exoskeletons. What could happen to those shells (exoskeletons) if the ph of the ocean continues to be lowered and acidic concentration increases? What could a lower ph do to the proteins and other organic molecules that make up the soft tissue (represented by the raw egg s inside material) of a marine organism PG. 5