National Agricultural Literacy Curriculum Matrix
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One in a Million
9 - 12
In this lesson, students will learn about solutes and solvents and will use serial dilution while investigating parts per million—a term used to describe the nutrient concentration of a fertilizer solution.
For the class:
- Two 250 ml beakers
- One roll of paper towels
- One box of food coloring, exclude yellow
- Colored pencils or crayons
- Optional: Becker Bottle (Flinn Scientific, Inc.)
For each group:
- One white ice cube tray (or well reaction plate with 12 wells)
- One permanent marker
- One eye dropper
- One 1 liter beaker
- Three small plastic cups
For each student:
- One in a Million lab worksheet
Essential Files (maps, charts, pictures, or documents)
- Answers to Commonly Asked Questions (additional information)
- One in a Million
- Answer Key- One in a Million
parts per million (ppm): a unit of measurement commonly used to describe the nutrient concentration in fertilizer solutions; can also be used to analyze contaminants in food, groundwater, air, and more. Compare to one drop of water in a swimming pool
solution: a type of homogeneous mixture in which the particles of one or more substances (the solute) are distributed uniformly throughout another substance (the solvent)
solute: the substance dissolved in a solvent to form a solution
concentration: the ratio of the mass or volume of a substance (solute) to the mass or volume of the solvent or solution
mixture: combination of two or more different substances which are not chemically bonded and can be a solid, liquid, or gas
Background Agricultural Connections
Interest Approach – Engagement
- Show students a two-minute video highlighting the career of a greenhouse manager.
- Ask your students what value a greenhouse has to plant production. Through class discussion and your explanation, help students understand that greenhouses help to optimize plant production. In a greenhouse, perfect or nearly perfect temperatures, moisture, and soil nutrients can be used to grow the best crops. Many ornamental crops are grown in greenhouses such as annual and perennial flowers. However, fruits and vegetables can also be grown in a greenhouse.
- Inform your students that they will be learning how farmers manage the application of fertilizer to provide adequate plant nutrients. Students will:
- learn about solutes and solvents; and
- use serial dilution and understand parts per million measurements.
Activity 1: Introduction
- Ask the class if they have ever used a powdered concentrate to create a beverage, such as hot chocolate or fruit punch. Explain that whether they realized it or not, they were creating a mixture. A mixture is a combination of two or more different substances, which are not chemically bonded, and can be a solid, liquid, or gas. Explain that there are two types of mixtures: homogeneous (also called solutions) which are uniform and particles are not typically seen, and heterogeneous mixtures which are not uniform and in which the particles can be seen.
- As a demonstration, add two tablespoons of salt to a 250 ml beaker of water and stir. Explain that the mixture is a homogeneous solution, meaning that the molecules within the solution, in this case water and table salt, are evenly distributed and look the same throughout.
- Add two tablespoons of sand to a 250 ml beaker of water and stir. Have students compare and contrast the two mixtures. Ask students to describe the difference between the sand and water mixture and the salt and water mixture. Explain that the sand and water mixture is a heterogeneous mixture, meaning that the molecules will not be evenly distributed throughout the liquid.
- Explain that in agriculture, fertilizer solutions are one way that farmers supply their crops with essential plant nutrients. In science terms, the solute is the fertilizer added to the water. The water is the solvent, which does the dissolving. The solution more or less takes on the characteristics of the solvent. The concentration of a fertilizer solution is defined by the amount of fertilizer (solute) dissolved in water (solvent).
Activity 2: Parts Per Million
- Ask students to raise their hands if they’ve ever heard the term “one in a million.” Discuss what the term means and why people say it.
- Build on the classroom discussion by explaining how unique “one in a million” really is. Show students a “One in a Million” Becker Bottle to illustrate the concept. This three liter bottle contains one million tiny colored spheres. Each colored sphere represents a different quantity, or concentration. The yellow spheres represent 100,000 in a million, the red spheres represent 10,000 in a million, the white spheres represent 1,000 in a million, the pink spheres represent 100 in a million, and the green spheres represent 10 in a million. The single black sphere in the bottle represents one in a million, or in scientific terms, one part per million. Explain that today the class is going to investigate the scientific concept of “parts per million”—a unit of measurement used to describe a very small amount of material.
- Explain that in the scientific community, parts per million is expressed as “ppm.” Parts per million is the unit of measurement commonly used to describe the nutrient concentration in a fertilizer solution. It can also be used to analyze contaminants in food, groundwater, air, and more.
- Introduce the lab by explaining that students will use a dilution activity to create and investigate solution concentrations. Review laboratory safety instructions. Distribute and review the One in a Million lab worksheet. Divide the class into pairs or triads, and direct students to the necessary materials.
- After students complete the dilution lab activity and the One in a Million lab worksheet, use a classroom discussion to debrief their findings. Discussion points may include:
- Good fertilizer practices that match fertilizer inputs to crop nutrient requirements will achieve high-quality, economically sustainable yields and will protect the environment. Arable land available for growing food will continue to diminish as population growth continues. Efficiently managing inputs, such as water and fertilizer, will be essential to feeding a growing population.
- Improperly applied fertilizer can lead to environmental problems. It is important for anyone who applies fertilizer to follow application instructions. Farmers and researchers are constantly testing and implementing new methods for high precision use of fertilizers.
- Fertilizer is expensive. It is in the farmer’s best interest to apply the correct amount of fertilizer, supplying the plants with only the nutrients they need.
Concept Elaboration and Evaluation:
After conducting these activities, review and summarize the following key concepts:
- Nutrients found in the soil are key to good plant growth.
- If nutrients do not exist in soils, they can be added with fertilizers.
- The proper amount of fertilizer is best for the farmer and the environment.
- Create a Venn diagram to capture the differences and similarities of homogeneous and heterogeneous mixtures.
- Use an overhead projector to demonstrate complex math problems.
Offer an incentive for students who locate (and show you) the black sphere in the Becker Bottle.
Review your city’s annual water quality report. All public water systems are required to sample their source water and treated water for the presence of biological, inorganic, organic, and radioactive constituents. This report typically uses parts per million and parts per billion to summarize constituent levels. Look up and define unknown terms and summarize key findings.
One part per million is equivalent to one hole in 55,555 rounds of golf! Put a million into perspective by challenging students to use the factor-label method to convert one part per million (or one part per billion) to a number that is meaningful to them. Consider expressing the unit of measurement in seconds, miles, U.S. population, etc.
Suggested Companion Resources
- Everything is Chemical (Multimedia)
- Feeding the World and Protecting the Environment (Multimedia)
- Phosphate Mining Video (Multimedia)
- Potash Mining Video (Multimedia)
- Science of Soil Digital Explorations (Multimedia)
- How a New Evolutionary Map Could Help Farmers Eliminate Fertilizer (Website)
Agricultural Literacy Outcomes
Culture, Society, Economy & Geography
- Describe essential agricultural careers related to production, consumption, and regulation (T5.9-12.d)
Education Content Standards
Plant Science Systems Career Pathway
PS.01.03Develop and implement a fertilization plan for specific plants or crops.
HS-ETS1: Engineering Design
HS-ETS1-2Design a solution to a complex real-world problem by breaking it down into smaller, more manageable problems that can be solved through engineering.
Common Core Connections
Reading: Anchor Standards
CCSS.ELA-LITERACY.CCRA.R.3Analyze how and why individuals, events, or ideas develop and interact over the course of a text.
CCSS.ELA-LITERACY.CCRA.R.7Integrate and evaluate content presented in diverse media and formats, including visually and quantitatively, as well as in words.
CCSS.ELA-LITERACY.CCRA.R.9Analyze how two or more texts address similar themes or topics in order to build knowledge or to compare the approaches the authors take.
Speaking and Listening: Anchor Standards
CCSS.ELA-LITERACY.CCRA.SL.1Prepare for and participate effectively in a range of conversations and collaborations with diverse partners, building on others’ ideas and expressing their own clearly and persuasively.
Mathematics: Practice Standards
CCSS.MATH.PRACTICE.MP1Make sense of problems and persevere in solving them. Students start by explaining to themselves the meaning of a problem and looking for entry points to its solution. They analyze givens, constraints, relationships, and goals. They make conjectures about the form and meaning of the solution and plan a solution pathway rather than simply jumping into a solution attempt. They consider analogous problems, and try special cases and simpler forms of the original problem in order to gain insight into its solution. They monitor and evaluate their progress and change course if necessary. Students check their answers to problems using a different method, and they continually ask themselves, “Does this make sense?” They can understand the approaches of others to solving complex problems and identify correspondences between different approaches.