Does clay trap more spilled oil than sand does? You pour equal amounts of three liquid pollutants through two types of soil and measure how much each soil absorbs in 60 seconds. The pollutants are oil, gasoline, and antifreeze.
Clay absorbed an average of 220 milliliters of oil out of 250. Sand absorbed only 126 milliliters. Thinner liquids like gasoline and antifreeze passed through both soils much faster than thick oil did.
The results help explain why some soil near polluted areas stays contaminated longer than others.
Hypothesis
The hypothesis is that the soil with less porosity will be most absorbent.
Not all soil types hold pollutants the same way. Clay traps far more spilled oil than sand does, making some ground more unsafe than others. This project pours equal amounts of oil, gasoline, and antifreeze through two soil types and measures absorption in 60 seconds.
When a material soaks up a liquid and holds it inside, that's absorption in action. In this experiment, you pour equal amounts of oil, gasoline, and antifreeze through sand and clay, then measure how much each soil absorbs in 60 seconds. The results are striking: clay soaked up 220 milliliters of oil out of 250, while sand absorbed only 126 milliliters.
Method & Materials
You will measure the amount of pollutants that filter through 250 mg of soil, and compare the results for different types of soil and pollutants.
You will need a plastic filter, sand, clay, oil, gasoline, antifreeze, plastic cups, a graduated cylinder, scratch paper, and a stopwatch.
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The results of the experiment showed that the oil and clay combination was the most absorbent, with an average of 220.33mL of oil, 112.33mL of antifreeze, and 132.33mL of gasoline absorbed. The sand absorbed an average of 126mL of oil, 146.33mL of antifreeze and 138mL of gasoline.
Why do this project?
This science project is interesting because it can help farmers, gardeners, and botanists better understand absorbency in different types of soil, which can help them with soil pollution problems.
Also Consider
Variations to consider include testing different types of pollutants, and testing different amounts of soil.
Full project details
Additional information and source material for this project are available below.
