| Explore | Concerning celery and osmosis, I have learned that, with exposure to water with low salt concentrations, the celery can become hypertonic and possibly stiffen and that, when celery is exposed to water with larger concentrations of salt, the celery grows soft and becomes hypotonic. Also, I have learned that different parts and cells of celery perform osmosis differently. |
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| Research Question | Will a 4-inch piece of celery in a cup of water with 2tbsp of salt naturally bend more than a 4-inch piece of celery in a cup of water with 4tbsp of salt when both cups are set in the fridge for 30 hours and contain one cup (here a cup is a measurement) of water? Considering how celery became more flexible when placed in cups of water with 2 tbsp of salt and 4 tbsp of salt for 24 hours, my group wondered if the celery would have naturally bended if the celery had been in the salt water for a longer amount of time than 24 hours. |
| Predictions | I believe that the cup of water and celery with 2tbsp of salt will curl more than the cup of water and celery that contains 4tbsp of salt when both cups are placed in the fridge for 30 hours (a hypothesis of sorts). I think that the piece in water with 4tbsp of salt may become too soft to keep a bent shape. |
| Experimental Design | 2 cups of water, two 4-inch pieces of celery, 2 clear cups, and 6 tbsp of salt are needed for the experiment. The independent variable will be that one clear cup of water contains 2tbsp of salt while the other contains 4tbsp of salt; the control variable, the celery pieces and the dependent variable, the amount of curl in each of the celery pieces. Two group members will run the experiment for a total of two trials. To run the lab there are a few steps. First, 2 clear glasses of water will each be filled with 1 cup of water. Second, 2tbsp of salt are added to one cup while 4tbsp of salt are added to the other. Third, a 4-inch piece of celery will be fully placed into each cup. Fourth, both cups will be placed into the refrigerator for 30 hours. Fifth, when the 30 hours end, the pieces of celery will be taken out of the clear cups and compared to see whether one piece curled more than the other. |
| Conclusion | Neither of our celery pieces curled, so the answer to our question would be that a 4-inch piece of celery in a cup of water with 2tbsp of water does not naturally bend more than a 4-inch piece of celery in a cup of water with 4tbsp of salt. We believe that the celery did not bend was possibly due to the fact that our celery did soften. Perhaps, the celery pieces became too soft and could not bend/keep a bent shape on their own. |
| Investigation Theme | CEL |
| Grade Level | High School Students (Grades 9,10,11,12) |
| School Name | Ottawa Township High School |
| Session | Fall 2020 |