Unit 7.3, Lesson 5: Synthesizing a Synthetic
This page contains the primary outline of a Mi-STAR lesson, which is just one part of a larger 7th grade unit.
- All synthetic materials are made from natural resources that come from the Earth.
- Natural resources are processed through chemical and physical changes to create the synthetic materials humans use.
- How are substances processed to make synthetic materials?
- Where do these substances come from?
In previous lessons within Unit 7.3, students have learned the difference between physical and chemical properties, how these properties relate to thermal energy transfer, and how these properties can change as materials are processed by humans. In this lesson, students will think critically about the process of synthesizing the materials we use in our everyday lives.
- Semester Unifying Crosscutting Concept: Energy & Matter
- SEP: Science & Engineering Practices
- Obtaining, Evaluating, and Communicating Information
- DCI: Disciplinary Core Ideas
- PS1.B: Chemical Reactions: Substances react chemically in characteristic ways.
- PS1.A: Structure and Properties of Matter: Each pure substance has characteristic physical and chemical properties.
- CCC: Crosscutting Concepts
- Structure and Function
- CCC: Crosscutting Concepts
- Energy and Matter: Matter is conserved because atoms are conserved in physical and chemical processes. (MS-PS1-5)
Students will be able to:
- obtain and synthesize information that describes how synthetic materials, via physical and chemical processes, come from natural resources.
- construct an explanation from evidence to determine if a chemical reaction (a rearrangement of atoms) has occurred by identifying new chemical and/or physical properties.
- construct explanations for the chemical reaction of substances and the creation of synthetic materials based on evidence of change in their physical and chemical properties.
- Teaching Time: 3-4 Class Periods (assuming 50 minute periods)
- Instructional Setting: Classroom; Access to Computers with Internet Access
Students inspect a variety of natural and human-made materials and speculate as to their origin, those from the Earth and those not from the Earth. This activity builds toward the lesson questions: How are substances processed to make synthetic materials? Where do these substances come from?
7.3_L5_LessonSlides_ex (not active)
Students will create a synthetic material, flubber, from the mineral borax and glue. As students will come to recognize in the “Share your Idea” phase they are conducting chemical reactions. The ingredients are reactants and the resulting flubber is the product though these terms should not be introduced to students until later in the lesson. Students investigate how the properties of the reactants change as a result of mixing them. Students observe that by varying the concentration of reactants (glue and borax solution) in a mixture, the physical properties of the product (flubber) will also change. Students analyze the properties of each of the resulting four batches of flubber. Students notice that changing the amounts of each ingredient will produce a product with different properties. Students also observe that all of the ingredients combined in the mixture are part of the product. As a class, students select a concentration of the ingredients that creates flubber with properties desirable to the class.
Students develop explanations for the concepts and practices uncovered during their investigation of flubber in order to better understand the lesson question. Students will obtain and evaluate information from multiple sources (print, Internet, or textbooks) as needed to develop their explanations using evidence-based reasoning from their flubber investigation and includes the necessary science and engineering terminology. Throughout this instructional phase, students will develop a lesson level “Gotta Have Checklist” (Note: You can work with students to develop this list using the ‘components of a Gotta Have Checklist’ or you may choose to give it to the students). To develop this checklist the teacher will facilitate students’ reflection on the properties of the reactants and products of the Flubber. Students then construct an explanation of why some properties change using a simplified chemical equation of the process. Students develop an argument for whether flubber is a synthetic material or not by considering whether chemical reaction has taken place during the manufacturing process. By the end of this instructional phase students will use the “Gotta Have Checklist” to revisit the “What did we do?” column and complete the “What evidence did we gather?” column for this lesson on the Unit Summary Table.
Students connect back to the Unit Challenge in this phase. Individual students or unit challenge groups gather information from ‘How its Made’ Videos highlighting the manufacturing processes and the natural resources and other materials needed to create their insulation material. Students consider the credibility, possible bias, accuracy, and relevancy of the sources to support an argument. Then, using the Student Guide located in the resources section below, students will identify the reactants and products involved in the manufacturing process, describe the physical and/or chemical changes that have occurred, and identify how the altered structure of the material enhances its useful function. Students will communicate what they have learned by developing a simplified chemical equation of the manufacturing process for their insulation material. The students will revisit the “What evidence did we gather?” column and complete the “How does this evidence relate to the Unit Challenge” column in the evidence did in the Unit Summary Table. The knowledge that students build in the phase will also be used to update the manufacturing stage of the Life Cycle model of their insulation material. Students will discover that primary natural resource from which their insulation material is derived.
Students will complete a three dimensional Mi-STAR embedded assessment associated with this phase. Instructions on how to implement and score the Embedded Assessment are included in the accompanying resource linked below. During the Embedded Assessment students will individually check their progress of the learning performances by gathering and synthesizing information about two provided synthetic materials and answering the lesson questions: “How are substances processed to make synthetic materials? Where do these substances come from?” Depending on the preferences of the teachers facilitating this lesson the students may use the lesson Gotta Have Checklist as a resource to develop their explanations or may be asked to create these explanations on their own.
Resources Needed for this Instructional Phase:
CARS (external link)