Chemistry of Materials

Chemistry of Materials 13: The Impact of Plastics on Society

Students gather, read, and synthesize information from text and diagrams about four types of polymers (Teflon, Kevlar, compostable polymers, and polyester). Students apply this information to an analysis of the impact of these materials on society, focusing on the crosscutting concepts of structure and function and connections to engineering, technology, and applications of science. Students also bring together their understanding of substances and their properties from this unit with information about the impacts of these materials on the environment. They use this synthesized knowledge to debate the trade-offs and help the Pasadena city council at an imaginary council meeting analyze competing proposals for reducing the use of single-use disposable plastics in Pasadena restaurants.

Improving Hip Replacements
Learn how materials scientists developed improved plastics for hip replacements.

Plastic Pollutants Pervade Water and Land
An article on the effects of plastics on different ecosystems.

Chemistry of Materials 12: Modeling Polymers

Students construct models to study the structure of polymers. Students used single paperclips to model monomers, chains of paper clips to model polymers and paperclip matrices to model cross-linked polymers. Manipulating the models helps them understand how the physical properties of a polymer result from its structure. In a second type of model, the class acts as a polymer, with student pairs representing monomers. Students identify the strengths and weaknesses of the models to represent polymers and cross-linking.

Chemistry of Materials 11: Making Polymers

Students conduct an investigation in which they cross-link a polymer and analyze the results by comparing the starting and final substances. This reinforces the characteristic properties of each pure substance while introducing chemical change. The crosscutting concepts of structure and function and connections to engineering, technology, and applications of science are related to the design and impact of engineered products. Having previously investigated properties of two plastics, students cross-link polyvinyl alcohol with sodium borate to produce a third polymer similar to the one known commercially as Slime. Students are introduced to synthetic chemistry and chemical change as they compare the properties of the starting substances and the product they developed through a chemical cross-linking reaction.

American Chemistry Council
Every week this site is updated with “new innovations in plastics that contribute to sustainability, safety, longer lives and better performance.”

Environmental Health News
This page has an article on the environmental toll of plastics.

Ecology Center Plastics Report
Common misconceptions related to plastic production and recycling are explained on this webpage.

Scientific American
An article on how plastics are versatile materials but they can harm the environment and human health.

Plastics Industry
A webpage that discusses plastics and the environment.

Plastic Pros & Cons
This website discusses many of the postive and negative aspects of plastics.

Great Pacific Garbage Patch
This article discusses recent estimates for the size of the Great Pacific Garbage Patch, which is composed mostly of plastic debris.

Chemistry of Materials 10: Modeling State Changes

Students carry out an investigation to collect data about the relationships between temperature and state changes. Students record the temperature of water over time as they freeze it and then as the ice melts. Students graph their data to produce curves that show the freezing and melting temperatures of water. They analyze and interpret these data in order to construct explanations about what is happening to particles during state changes. Students further develop their models depicting particle movement, temperature, and state, including the role of thermal energy.

Chemistry of Materials 9: Energy and Particle Movement

Students carry out investigations to collect data about how temperature and kinetic energy relate to gas particles. Students investigate cause-and-effect relationships between adding or removing thermal energy to raise or lower temperature, and explore the movement of gas particles. Students investigate the effect of temperature on gas particles through two different investigations. In the first investigation, they observe what happens to a soap film when the container is submerged in hot and ice water. In the second investigation, they observe what happens to air and water inside of a syringe that is submerged in hot, room-temperature, and ice water. They use their new understandings to further refine their models about particles in different states to include kinetic energy.

Chemistry of Materials 8: What's in a State

Student groups discuss the three states of matter and the characteristics of each. Students examine syringes filled with materials in each state and predict and test whether they can compress each substance. Students then use a simulation to investigate the particles in each substance—how they move and how they interact with each other. Throughout this activity, students draw and revise models of the particles in each state. Students make observations and construct explanations about how the behavior of the particles in each state causes the observable properties of solids, liquids, and gases. Finally, students use a computer simulation to gather more information to begin developing models of the particles in solids, liquids, and gases.

Chemistry of Materials 7: Structure and Properties of Materials

Using information from text and diagrams of structural models, students elaborate on what they observed from developing models of molecules and extended structures in the “Modeling Molecules” activity.  They used Pear Deck, an interactive slideshow, to navigate though the text. This activity emphasizes the crosscutting concept of scale, proportion, and quantity as students observe the varieties of particles that make up substances. The activity also focuses on the crosscutting concept of structure and function, building the concept that the particle structure of a substance determines its bulk properties and how the substance can be used. Students then sketched and explained a molecular model showing extended structures of different densities. 

Chemistry of Materials 6: Modeling Molecules

Students are introduced to the practice of modeling as a tool to investigate phenomena at a molecular scale. Students begin to explore the organization of atoms and molecules as they use models to investigate atoms, elements, chemical bonds, molecules, and compounds.

Chemistry of Materials 5: Evaluating Properties of Materials

Students read and synthesize information from multiple sources on the use of materials and their potential impact on society, and they assess the credibility and possible bias of these sources. Students use this and additional information to inform a debate on which material would be best for the intended purpose (as a reusable drink container), in terms of both its structure and function and its impact on society.

Chemistry of Materials 4: Determining Density

Students conduct an investigation to collect, analyze, and interpret data on density for several materials—aluminum, glass, and four types of plastics. Students connect their analysis of the densities of these materials to the possible uses of each, focusing on the crosscutting concept of structure and function. They determine the volume and mass of six samples—aluminum, glass, and four types of plastics—and then calculate the density of each sample. Based on their calculations, they predict if the samples will sink or float in water and then test their predictions.

Chemistry of Materials 3: Physical and Chemical Properties of Materials

Students are introduced to compounds and to the chemical properties of materials. Students explore the properties of several materials, including compounds and elements.  Students conduct an investigation with several materials and use the data to determine how properties of a specific material would determine its use, focusing in particular on structure and function. They look at density relative to water, solubility in water, and reactivity, and they analyze data on melting point, boiling point, and flammability.

Chemistry of Materials 2: Investigating Elements

Students investigate the physical properties of a set of elements. They investigate physical properties including appearance, malleability, density, and solubility in water at room temperature. They analyze and interpret the data they collect on these elements and begin to explore how this data can help identify pure substances. They are introduced to the concept that each element is composed of a specific type of atom. Finally, students assess how their new data can be used as evidence to determine if aluminum is a good choice for making a drink container.

Visit the sites below to view the Periodic Table of Elements.

Chemistry of Materials 1: Exploring Materials

To begin the Chemistry of Materials unit, students brainstormed questions to add to our Driving Question Board. They thought about the Unit Issue, "What properties of materials might determine their uses? What kind of effects might the use of these materials have on the environment?" and the Anchoring Phenomena, "Different materials are used for different purposes." Then students generated questions.  After sharing out their questions, they wrote the question they most want to answer on a sticky note. We then looked at the three driving question for the Chemistry of Materials Unit, and placed their questions near the driving question closest to their own. 

Students then brainstormed and discussed what they know about the properties of aluminum, glass, and plastic as materials for producing single-use drink containers. Materials like plastics, metals, and glass are all useful, but they can also affect the environment.  For many students, a priority in choosing a drink container, is the effect of the container material on the taste of the beverage. To investigate if students can really taste the difference, we did a blind taste test of Coca-Cola from three different containers. MS students in average could NOT reliably discern the difference between Coke out of an aluminum can, glass bottle or plastic bottle.  All the Coke was the American formula with high fructose corn syrup. 

They then discussed their current understanding of the advantages and disadvantages of each material and developed a list of questions needed to decide which is better for single-use drink containers. They then examined four graphs of data on the materials to help inform their choices. Students began to gather and synthesize information about the physical and chemical properties of three materials—glass, aluminum, and plastic. They then assessed how this information might be used as evidence for making a decision about which material to use for a drink container in relation to the structure and function of that object.