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Green Chemistry and the School Science Lab – Safer Chemistry for Today and Tomorrow

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Lessons and student projects to support educators and students learning about chemistry and experimenting with green chemistry principles in mind.

To make them safer and more environmentally-friendly, chemistry classrooms and labs are changing. Are your labs, chemistry demonstrations, and classroom experiments green? If not, read on to learn more and find green chemistry options to use with your K-12 students.

What is Green Chemistry?

Green chemistry reimagines chemical processes in ways that are environmentally aware, produce less hazardous waste, reduce pollution, and result in cleaner air and water and safer foods and products for everyone. Green chemistry involves designing chemical products and processes in ways that reduce or eliminate hazardous substances. This includes carefully evaluating which chemicals are used, assessing chemical reactions, and designing processes that don’t result in hazardous byproducts and waste that require cleanup.

The following video provides an introduction to green chemistry.

Making Chemistry Safer at School

To adopt, promote, and teach green chemistry practices, educators have to adapt and update lessons and experimental procedures and implement practices to make school labs places for green chemistry. The Environmental Protection Agency’s (EPA) defines 12 principles of green chemistry. These principles provide a checklist for evaluating the safety of chemistry experiments and thinking through the redesign or improvement of existing chemical processes. In shifting to green chemistry, scientists seek to:

  1. Prevent waste
  2. Maximize atom economy
  3. Design less hazardous chemical syntheses
  4. Design safer chemicals and products
  5. Use safer solvents and reaction conditions
  6. Increase energy efficiency
  7. Use renewable feedstocks
  8. Avoid chemical derivatives
  9. Use catalysts, not stoichiometric reagents
  10. Design chemicals and products to degrade after use
  11. Analyze in real time to prevent pollution
  12. Minimize the potential for accidents

For more information about these principles, see the Green Chemistry resource area at Science Buddies.

Make Your Next Chemistry Experiment ‘Green’

Thanks to sponsorship from Millipore Sigma and partnership with BeyondBenign, Science Buddies has NGSS-aligned lessons and independent student science projects to support educators and students as they learn about green chemistry and its importance for the environment, human health, and the future. The new Green Chemistry resource area at Science Buddie makes it easy to find resources for use with K-12 students. In this area, educators and students will find resources like the following:

NGSS-Aligned Lessons for Green Chemistry

  • E-factor: Environmental Impact Factor for Chemical Reactions: in this lesson for middle and high school, students do a hands-on activity with M&Ms to learn what environmental impact factor (E-factor) is, how it applies to chemical processes, and how waste from chemical reactions can be reduced by applying the principles of green chemistry. Which principles of green chemistry are involved? Use of catalysts, use of renewable feedstocks, avoiding chemical derivatives, and real-time analysis for waste.
  • Chemical Reactions: What is Plastic Made From?: in this self-paced middle school video lesson, students do a milk-to-plastic experiment and learn about chemical reactions, polymerization, and how a new product can be created from a chemical reaction. Which principles of green chemistry are involved? Use of renewable feedstocks and designing chemicals and products to degrade after use.
  • Recycling PLA Plastic using Green Chemistry: in this high school lesson, students learn about polylactic acid (PLA) plastic (“corn plastic”). They explore the biodegradation of PLA compared to other plastics and experiment with using saponification to transform PLA into lactic acid.
    Which principles of green chemistry are involved? Waste prevention, less hazardous chemical synthesis, and use of renewable feedstocks.
  • Using Green Chemistry to Understand Types of Chemical Reactions: in this lesson, high school students learn about different reaction types, including composition, decomposition, single-displacement, and double-displacement reactions. Using the 12 Principles of Green Chemistry as a guide, they are then challenged to identify reaction types and choose which reactions they will create. Which principles of green chemistry are involved? Waste prevention, less hazardous chemical synthesis, energy efficiency, use of renewable feedstocks, catalysis, designing for degradation, and reducing the potential for accidents. This lab replaces traditional reaction experiments involving chemicals such as lead (II) nitrate, barium chloride, and silver nitrate with greener alternatives.
  • Turn Milk into Plastic!: in this middle school lesson, explore the process of making casein plastic from milk.
    Which principles of green chemistry are involved? Use of renewable feedstocks and designing chemicals and products to degrade after use.
  • Make a Dye-Sensitized Solar Cell: in this high school lesson, students build and test their own dye-sensitized solar cells using dye from blackberries. Which principle of green chemistry is involved? Designing less hazardous chemical syntheses.

Science Projects and Activities to Explore Green Chemistry

  • Investigate the Kinetics of the Color Changing Iodine Clock Reaction: use a modified iodine clock reaction for a green chemistry demonstration. Watch as reactants are mixed to create a solution that changes color and then experiment to determine how the reaction rate changes relative to the hydrogen peroxide concentration. (This student science project is a green chemistry variation of a classic iodine clock reaction.)
    Which principles of green chemistry are involved? Waste prevention, less hazardous chemical synthesis, and reducing the potential for accidents.
  • Go Green by Growing Green: How to Extract Energy from Grass: students grow three different types of grasses and investigate which grass produces the most biomass and energy.
    Which principle of green chemistry is involved? Use of renewable feedstocks.
  • From Trash to Gas: Biomass Energy: students compare the amount of biogas produced from different types of biomass.
    Which principle of green chemistry is involved? Use of renewable feedstocks.
  • Turn Plants into Biofuel with the Power of Enzymes: explore the use of enzymes (like cellulobiase) to create effective chemical reactions with ethanol-based biofuels (like cellulosic ethanol).
    Which principles of green chemistry are involved? Use catalysts not stoichiometric reagents and use renewable feedstocks.

The following video is from the Investigate the Kinetics of the Color Changing Iodine Clock Reaction independent student science project, which has been updated to reflect principles of green chemistry:

Green Chemistry Today for Tomorrow

As today’s students learn about and experiment with chemistry, they have the opportunity to seek, adopt, and prioritize green chemistry from their very first experiments. With the right guidance, resources, and examples, their framework for chemistry can be green from the very beginning..

Note: The EPA has a downloadable bookmark you can print that lists the 12 Principles of Green Chemistry.

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