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E-factor

E-factor
Contributors
Mollie Enright
Beyond Benign, Inc.
Annette Sebuyira
Retired K-12 Educator | Beyond Benign, Inc.
Janie Butler
Fostering Learners + Leaders in Sustainable STEM | Science Done Sustainably
Beyond Benign
Beyond Benign, Inc.
Learning Objets
Summary
E-factor is a metric that measures the overall efficiency in terms of waste generation of a chemical reaction. E-factor stands for the "Environmental Impact Factor" and is the ratio of how much waste is produced per unit of product made:

E factor= (mass of waste produced (g))/(mass of isolated product (g))

As a result, the lower the E-factor, the more sustainable and less wasteful the reaction is (with the lowest possible value being zero). This is a metric commonly used in industrial settings and a skill that can be applied to other labs done in your classroom.

In lab settings, students can apply the concept of E-factor to evaluate the efficiency of chemical reactions they perform. E-factor is an important concept in green chemistry because it encourages students to think about the environmental impact of chemical reactions and promotes the development of sustainable chemical processes. E-Factor relates to other green chemistry metrics including the 2nd Principle of Green Chemistry, Atom Economy.
Keyword Tags
Atom Economy
Percent Yield
Environmental Impact Factor
12 Principles of Green Chemistry
File (PDF, PPT, image, etc)
e-factor-lab.docx
Digital Object Identifier (DOI)
https://doi.org/10.59877/EGLM5581
Learning Goals/Student Objectives
Educational Goals: To understand the application of the E-Factor to everyday life and its use in chemical processes.

Student Objectives: Students will…
• Use models to practice calculating E-factor
• Relate E-Factor to chemical processes
• Explore an example of the use of E-factor in industry
Object Type
Laboratory experiment
Audience
High School (Secondary School)
Common pedagogies covered
Hands-on learning
Green Chemistry Principles
Atom Economy
Safety Precautions, Hazards, and Risk Assessment
Do not allow students to eat food materials that come in contact with any lab equipment or contaminated surfaces.
Teacher Recommendations or Piloting Data (if available)
Use the bulk bag of M&M’S to prepare five baggies of M&M’S as shown in the table below. The green M&Ms represent a unit of mass of the desired product, whereas all other colored M&Ms represent the waste. Baggies of M&M’s do not need to be precise ratios, but should range in the ratio of green M&M’s to other colored M&M’s. For example, one bag should look similar to the exemplar in the table next to petrochemicals with a composition being mostly green M&M’s, while another bag modeling pharmaceuticals should only have approximately one green M&M in it.

Bag C Ratio: 10 green: 1 non-green
Bag B Ratio: 1 green: 4 non-green
Bag A: 1 green: 20 non-green
Bag D:1 green: 250 non-green
NGSS Standards, if applicable
• HS-ETS1-1. Analyze a major global challenge to specify qualitative and quantitative criteria and constraints for solutions that account for societal needs and wants.
• HS-ETS1-2. Design a solution to a complex real-world problem by breaking it down into smaller, more manageable problems that can be solved through engineering.
• HS-ETS1-3. Evaluate a solution to a complex real-world problem based on prioritized criteria and trade-offs that account for a range of constraints, including cost, safety, reliability, and aesthetics, as well as possible social, cultural, and environmental impacts.

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Submitted by

Rhianna Kozinski
Published on
Moderation state
Published
Time required (if applicable)
One 45-60 minute class period
Creative Commons License
Creative Commons License
This work is licensed under a Creative Commons Attribution-NonCommercial-ShareAlike 4.0 International License.