Green Chemistry Lesson Plan Grade

Green Chemistry Lesson Plan

Grade Level -- 8-10; some science background necessary in dealing with cellular respiration, acid, base, etc. (Note: can be extrapolated to higher grades)

"Biofuels" are transportation fuels like ethanol and biodiesel that are made from biomass materials. These fuels are usually blended with the petroleum fuels -- gasoline and diesel fuel, but they can also be used on their own. Using ethanol or biodiesel means we don't burn quite as much fossil fuel. Ethanol and biodiesel are usually more expensive than the fossil fuels that they replace, but they are also cleaner-burning fuels, producing fewer air pollutants. Unlike gasoline, pure ethanol is nontoxic and biodegradable; it quickly breaks down into harmless substances if spilled. However, chemical denaturants are added to fuel ethanol (in relatively small quantities) to make it undrinkable. Many of the denaturants that are used are toxic. Similar to gasoline, ethanol is a highly flammable liquid and must be transported carefully. Biodiesel is nontoxic and biodegradable. Compared to diesel fuel made from petroleum, biodiesel produces fewer air pollutants like particulates, carbon monoxide, sulfur dioxide, hydrocarbons, and air toxics. However, it does slightly increase emissions of nitrogen oxides. Biodiesel does not smell as bad as regular diesel fuel when it burns; sometimes biodiesel exhaust smells like French fries! Students will enjoy learning about environmentally safe energy, and gain a better understanding of the use of "green chemistry" in daily life (U.S. Energy Information Systems, 2009).

Who wrote this lesson -- name of all the people in your group?

Teacher Background Information: Students should have used the scientific method in previous student-created experiments. In addition, they should know lab safety rules. Students need also be familiar with photosynthesis and using either the Vernier Labpro or TI CBL equipment with either a computer or TI calculator. Equivalent products are acceptable.

Safety information: Preview experiment before beginning, never eat or drink in lab, never use mouth suction to extract chemicals, do not touch face, wear glasses/goggles, pull back long hair, wear aprons and gloves when required, wipe surfaces when done. (See: (Gerber, 2010).

Educational Goal: To understand: The environmental and economic benefits of ethanol as a fuel and to synthesize prior knowledge to a) maintain an experiment using the scientific method, b) understand the complex reactions between chemicals, and c) understand that green chemistry is an important tool in global sustainability.

Student Objectives: Students will:

Identify ethanol as a product of sugar fermentation

Know that photosynthesis produces complex carbohydrates (polysaccharides)

Understand that hydrolysis is a technique used by chemists to break apart polysaccharides into saccharides that can be fermented

Demonstrate that starch can be hydrolyzed by salivary amylase

Demonstrate appropriate safe laboratory behavior and technique while mixing chemicals

Follow correct procedures for using a colorimeter

Document observations and data in an organized appropriate laboratory format

Analyze and interpret the results of the colorimetric data and observations

Communicate their results orally

Materials: (per lab group -3 students): Protective eye wear, vinyl gloves, lab apron, graduated cylinder, 250 ml beaker, stirring rod, distilled water, 4-8-15 ml test tubes and stoppers, labels for glassware, waterproof pen, notebook, mass balance, weighing paper, kiwi wipes, disposable pipettes, graphic calculator or computer, corn starch, iodine tincture. Outside products: Vernier LabPro and Cords (LABPRO, $220), Colorimeter and cuvettes (COL-BTA $110) or equivalent (Products for Science Experiements, 2011).

Time required: This is set up as a week-long unit, five, 45 minute class periods or equivalent; one each for: 1) background information and discussion, 2) sulfuric acid tests, 3) saliva tests, 4) self-directed investigation, 5) discussion of results and conclusions/evaluation.

New Vocabulary Terms to review: ethanol, corn stover, hydrolysis, cellulose, hemicellulose, carbohydrates, polysaccharide, starch, saccharide, glucose, enzyme, salivary amylase, cellulose, colorimeter, cuvette, concentration, absorbance, wavelength, nanometer, fermentation, renewable resource, non-renewable resource

National Standards Met:

Science Content Standards: 8-12

CONTENT STANDARD A: Science as Inquiry As a result of activities in grades 8-12, all students should develop: 1) Abilities necessary to do scientific inquiry, 2) Understandings about scientific inquiry

CONTENT STANDARD B: Physical Science As a result of their activities in grades 8-12, all students should develop an understanding of: 1) Structure of atoms, 2) Structures and of properties in matter, 3) Chemical reactions

CONTENT STANDARD C: Life Science- 1) understanding of the cell

CONTENT STANDARD E: Science and Technology -As a result of their activities in grades 8-12, all students should develop: 1) Abilities of technological design, 2) Understandings about science and technology

CONTENT STANDARD F: Science in Personal and Social Perspectives As a result of activities in grades 8-12, all students should develop understanding of: 1) Natural resources,

2) Environmental quality, 3) Science and technology in local, national, and global challenges

CONTENT STANDARD G: History and Nature of Science As a result of their activities in grades 8-12, all students should develop understanding of: 1) Science as a human endeavor,

2) Nature of scientific knowledge

Green Chemistry Principles Addressed:

Prevention - It is better to prevent waste than to treat or clean up waste after it has been created.

Atom Economy - Synthetic methods should be designed to maximize the incorporation of all materials used in the process into the final product.

Less Hazardous Chemical Syntheses- Wherever practicable, synthetic methods should be designed to use and generate substances that possess little or no toxicity to human health and the environment.

Designing Safer Chemicals= Chemical products should be designed to affect their desired function while minimizing their toxicity.

Design for Energy Efficiency - Energy requirements of chemical processes should be recognized for their environmental and economic impacts and should be minimized. If possible, synthetic methods should be conducted at ambient temperature and pressure.