Students will conduct a soil study by investigating pH and water absorption.
Students will learn:
- How to describe the composition of soil and explain how it forms.
- That soil is made up of tiny particles of rock, plant, and animal matter.
- How to determine whether a solution is acidic, basic, or neutral.
- How scientists classify soils.
- That erosion is controlled by how well the soil retains water.
Procedure for pH probeware
- Hand out 3 soil samples per group in lidded glass jars (approximately 2 tablespoons of soil).
- Students write a description of each sample on their data table.
- Students pour 50mL of distilled water into each jar.
- Close jar and shake well 30 times.
- Let the soil sample settle for 3 minutes.
- Repeat steps 4 and 5 for each soil jar.
- Rinse the pH probe with the rinse bottle of distilled water.
- Place the pH probe in the liquid part of the soil and water mixture and briefly swirl.
- When the reading stabilizes, record the pH value in your data table (approximately 3 minutes).
- Recap the jar. Rinse the pH probe with the rinse bottle.
- Repeat steps 8 and 9 for each soil jar.
- Rinse the pH probe a final time and place cap on probe.
Procedure for Water Absorption
- Students place 3 tablespoons of soil on a piece of filter paper.
- Student 1 places filter paper/soil into the container with holes in the bottom
- Student 2 holds this container over a beaker.
- Pour 100mL of tap water through the soil, collecting the water in the beaker.
- Let the sample drip for 1 minute.
- Use the 100mL graduated cylinder to measure the amount of water in the bottom container. Record on your data table.
- Repeat steps 1 through 7 for each soil sample.
Analyzing your Data
- Have students complete the portion of the worksheet below the data table.
- Have a class discussion.
- Students can collect soil samples from home to bring in for testing.
- Students can graph their results on graph paper or using Excel's graphing feature.
- Students can research soil conservation.
The teacher will use the group discussion and worksheet as an assessment.