Soil pH
Recommended for grades 6–12.
Introduction
When you think of pH, you probably think of acidic and basic solutions. But soil can be acidic or basic, too. Soil pH, sometimes referred to as soil acidity, can be expressed using the pH scale. The pH scale ranges from 0 to 14. Soils with pH above 7 are basic or sweet. Soils with pH below 7 are acidic or sour. A soil with a pH of 7 is neither acidic nor basic, but is neutral.
The pH of soil is an important factor in determining which plants will grow because it controls which nutrients are available for the plants to use. Three primary plant nutrients – nitrogen, phosphorus, and potassium – are required for healthy plant growth. Because plants need them in large quantities, they are called macronutrients. They are the main ingredients of most fertilizers that farmers and gardeners add to their soil. Other nutrients such as iron and manganese are also needed by plants, but only in very small amounts. These nutrients are called micronutrients.
Objectives
In the Preliminary Activity, you will gain experience using a pH Sensor and learn soil pH measuring technique as you determine the pH of a soil sample.
After completing the Preliminary Activity, you will first use reference sources to find out more about soil pH before you choose and investigate a researchable question dealing with soil pH.
Sensors and Equipment
This investigation requires each of the following Vernier sensors and equipment (unless otherwise noted):
Additional Requirements
You may also need an interface and software for data collection. What do I need for data collection?
Download Experiment Preview
The student-version preview includes:
- Step-by-step instructions for the Preliminary Activity
- List of materials and equipment
Note: The experiment preview of the Preliminary Activity does not include essential teacher information, safety tips, or sample data. Instructions for Logger Pro and other software (such as LabQuest App or TI handheld software, where available) are on the CD that accompanies the book. We strongly recommend that you purchase the book before performing experiments.
Standards Correlations
See all standards correlations for Investigating Environmental Science through Inquiry »
Experiment 10 from Investigating Environmental Science through Inquiry Lab Book
Included in the Lab Book
Vernier lab books include a CD with word-processing files of the student instructions, essential teacher information, suggested answers, sample data and graphs, and more.