Strategies & Activities
The three foundational experiments (biodiesel, bioethanol, and water purification/filtration/distillation) will be performed first by the teacher. The first time that the lab is presented, students will observe the teacher properly building the setup, performing the experiment, disassembling the setup, cleaning the setup, and finally putting the equipment back in the correct location. The students will then create cartoons describing the setup, the experiment, and the disassembly, making sure to specifically label all of the equipment as well as identifying which (in their opinion) is the most important step. The second repeat of the experiment will have the students conducting the experiment on their own, guided by the teacher, with the focus on proper technique and lab safety measures. Students will do their first official 'lab write-up' with this experiment. The third and further repeats of the experiment will have the students manipulating variables and focusing on different learning objectives. The concept is simple: if the students do these labs repeatedly, they will feel comfortable enough to begin thinking critically and learning the objectives at a higher level, while gaining their hands-on lab skills. Further, once this confidence is present, then students will begin deciding which variables they would like to manipulate (if approved by the teacher for safety conditions) so that they can truly begin their own self-initiated inquiry lab experiments.
Lesson 1: Biodiesel
Biodiesel will be created from Waste Vegetable Oil. Pre-demonstration discussions will include a feasibility study (20) that has students exploring not only the uses for biodiesel and its byproducts, but the feasibility for use to replace diesel fuel (20).
For the initial lesson the teacher will demonstrate, over a timeframe of three days, how to make biodiesel. During all aspects of the biodiesel synthesis, the students will be observing and taking notes (See Table 3: Biodiesel Production Activity). The objective of this activity will be for the students to create a cartoon to demonstrate their knowledge of lab safety, process, procedures, and the equipment (See Table 4: Biodiesel Activity Assessment).
The following topics can be spiraled with this activity through the course of the year: Law of Conservation of Mass, Byproducts, Chemical vs. Physical Properties, Separation Techniques, Catalysts, Transesterification, Organic Molecules, Multiple Step Reactions, Compound Synthesis, Acids/Bases, Indicators, Titrations, and Stoichiometric Dimensional Analysis.
Lesson 2: Water Purification, Filtration, and Distillation
A water purification system will be created based on the patent model discussed. River and rain water will be collected, filtered, purified, and distilled using the purification and filtration model and a standard distillation setup. Students will become proficient in creating their own heating curves (with multiple chemicals overlaid), determining the boiling points of a liquid, empirically determining what the liquid is, creating their own batches of distilled water from tap water for other experiments, and efficiently setting up, performing, and taking down purification and distillation setups. Discussions about where distillation processes are used in life (water, sodas, coffees, fuels) will be infused through the repeated experiments. The following topics will be spiraled through the repetition of the experiment: Prediction of Outcomes, Writing a Hypothesis, Lab Safety, Identification of Equipment, Measurements, Significant Figures, Percent Yield, Percent Error, Concentration (Molarity), Molar Mass, Solubility, Polarity, Boiling Points, Melting Points, Phase Changes, Distillation, Chemical vs. Physical Properties, Condensation, Evaporation, Separation Techniques, and Elements vs. Compounds vs. Homogeneous Mixtures vs. Heterogeneous Mixtures.
This lesson will be demonstrated with two experiments, the first being a water purification and filtration setup, and the second being a standard distillation setup. The water should be purified with UV light before and after filtration (see Table 5: Water Purification and Filtration Activity: setup diagram). Once purified and filtered, the water should be transferred to a standard distillation setup, and distilled (see Table 6: Water Distillation Activity: setup diagram) The objective of this activity will be for the students to create a schematic of the water purification and filtration process as well as for a standard distillation setup. The schematic should demonstrate students' knowledge of lab safety, process, procedures, and the equipment (See Table 7: "Water Purification and Filtration Activity Assessment" and Table 8: "Water Distillation Activity Assessment").
Lesson 3: Bioethanol
Bioethanol will be created from raw materials (Corn Meal). Pre-demonstration discussions will include a discussion regarding the use of feedstock that competes with food production and how ethanol is currently being used (21).
For the initial lesson on bioethanol the teacher will demonstrate, over a timeframe of two weeks, how to make bioethanol. During all aspects of the bioethanol synthesis, the students will be observing and taking notes, with special attention also being paid to the fermentation process (See Table 9: Bioethanol Production Activity). The objective of this activity will be for the students to create a cartoon to demonstrate their knowledge of lab safety, process, procedures, and the equipment (See Table 10: Bioethanol Activity Assessment).
The spiral topics described in the biodiesel lesson can also be reviewed during this lesson. A new topic that can be introduced is fractional distillation. Differences between gasoline and diesel engines as well as their purposes will also be discussed.
Lesson 4: Biodiesel
Biodiesel will be created from Waste Vegetable Oil, but this time by the student and under close supervision from the teacher. Evaluation will be based on the students' abilities to follow the process, as well as on the lab write up submitted by the students.
Lesson 5: Water Purification, Filtration, and Distillation
A water purification, filtration, and distillation system will be created, but this time by the students and under close supervision from the teacher. Evaluation will be based on the students' abilities to follow the process, as well as determine what other methods and materials could be used to clean water.
Lesson 6: Bioethanol
Bioethanol will be created from corn meal feedstock, but this time by the students and under close supervision from the teacher. Evaluation will be based on the students' abilities to follow the process, as well as on the lab write up submitted by the students.
Conclusion Lesson of the Unit: Survival Using Everyday Chemistry
Our community has just been hit with a major hurricane. Support services are limited and you and your team (class) have been commissioned to assist in the recovery of vital services. Using materials that you find within your neighborhood, the classroom, construct a biodiesel processing unit, a bioethanol processing unit, and a water purification, filtration, and distillation system. You will be given valuable raw materials (1 knorr's jar of waste vegetable oil, 1 knorr's jar of river or rain water, 2 ounces of yeast, 2.25 kg of sugar, and 2.25 kg of corn meal). Besides building the processing units, you must create 1 clean knorr's jar worth of distilled, purified, and filtered drinking water, 1 jar of biodiesel, and 1 jar of bioethanol). The timeframe to complete the project is 2 weeks. Good Luck. Our survival depends on this.
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