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POGIL Laboratory Experiments. Place Date Facilitator(s ). Activity 1: Your Laboratory Experiences. Take out a piece of paper Divide the paper in half, labeling one half “Successful” and the other half “Horrible”. Consider All Your Laboratory Experiences as a Student and as an Instructor.
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POGIL Laboratory Experiments • Place • Date • Facilitator(s)
Activity 1:Your Laboratory Experiences • Take out a piece of paper • Divide the paper in half, labeling one half “Successful” and the other half “Horrible”
Consider All Your Laboratory Experiences as a Student and as an Instructor • Individually: • Identify a specific course-related laboratory experiment that was very successful, describe the experiment, and list three things that made it “successful.” • Identify a specific course-related laboratory experiment that was horrible, describe the experiment, and list three things that made it “horrible.” • (3 min)
Common Laboratory Experiences • Discuss your “successful” and “horrible’ laboratory experiments within your group. Try to find any common characteristics. • Identify three significant characteristics (preferably that you have in common) for the successful experiments and three significant characteristics for the horrible experiments. • Be prepared to report out your list. • [7 min]
Question of the Day:How is the structure of a molecule related to its boiling point? • Boiling point can be thought of as a measure of the strength of attractions between molecules in a liquid. • Some potentially useful information
Question of the Day:How is the structure of a molecule related to its boiling point? • Boiling point can be thought of as a measure of the strength of attractions between molecules in a liquid. • Individually list five relationships between molecular structure and boiling point. (e.g., the larger the X, the higher the boiling point; the more Y, the higher the boiling point; the longer the name, the higher the boiling point, etc). • [2 min] • Within your group your manager will lead a discussion of your lists and the preparation of a prioritized list of these relationships. Your presenter will be called upon to report out your results. • [3 min]
Question of the Day:How is the structure of a molecule related to its boiling point? • Reporting Out
Question of the Day:How is the structure of a molecule related to its boiling point? • Typical student responses • Molecular weight • Shape • Size • Kind of atoms • Strength of bonds • Number of atoms • Number of bonds • Types of bonds • What experiment(s) would needto be conducted to test these hypotheses? • What apparatus and what reagents would be needed?
Boiling Points of Liquids • Group #1 • (hydrocarbons of varying length) • pentane • hexane • heptane • decane • Group #2 • (hydrocarbons of varying length with OH) • 1-propanol • 1-butanol • 1-pentanol • 1-hexanol • Group #3 • (hydrocarbons of varying length with C=O) • acetone • butanone • 3-pentanone • 2-heptanone • Group #4 • (4 or 5 carbons; 1st 3 nearly identical MW) • pentane • 1-butanol • butanone • 1-pentanol • Group #5 • (5 or 6 carbons; last 3 almost identical MW) • pentane • hexane • 3-pentanone • 1-pentanol • Group #6 • (first pair, last pair: almost identical MW) • acetone • 1-propanol • 3-pentanone • 1-pentanol
Analysis of Your Group Data • Examine the data in your group and determine if there are any trends. If so, discuss what those trends mean. • Which one of the possible hypotheses seems most likely based solely from your group data? • Which of the possible hypotheses can be rejected based solely from your group data? • [5 min]
Possible Further Extensions • Use molecular modeling to investigate relationship of structure to dipole moments and boiling point. • Predict (and measure) the boiling points of other liquids. • Note that 2-butanol (100°) and 1-butanol (112°) have different boiling points. Is this a general difference between 1- and 2- alcohols? How does placement of the OH group influence boiling point?
Student Outcomes • As a group: • Identify one laboratory skill that is developed and one content learning objective for the boiling point experiment. • [2 min]
The POGIL Laboratory Experience • What distinguishes a POGIL laboratory experience from a traditional laboratory experience?
The Traditional Laboratory • In many traditional laboratory settings, a concept that has been previously introduced in class, or presented as part of the pre-lab preparation, is confirmed or verified through the “experiment.”
Distinguishing Characteristics of “Verification” Laboratories Identified by College Chemistry Students • The instructor is concerned with the correctness of data. • The instructor lectures the whole class. • During laboratory the students record information requested by the instructor • The laboratory experiments develop skill in the techniques or procedures of chemistry. • Students usually know the general outcome of the experiment before doing the experiment. • Abraham, M.R. (1982). A descriptive instrument for use in investigating science laboratories. Journal of Research in Science Teaching, 19(2): 155–165
The POGIL Laboratory • Laboratory work is performed in advance of classroom work on underlying principles (limited background). • Students work in self-managed teams to conduct experiments rather than exercises that verify previously taught principles. • During a pre-lab session (real and/or virtual) the instructor poses a focus question or Question of the Day (QOD) and students propose a set of tentative answers. • Students do NOT all perform the identical experiment • Data is combined from multiple students to uncover general trends or concepts, and address the QOD.
Pre-Lab Session • Provides focus and structure; gets everyone involved • Focus question (Question of the Day) • Solicit hypotheses or predictions from students • Discuss appropriate experimentsWhat is expected for each hypothesis
Data Collection • Students collect data, with different students measuring related phenomena but with appropriate variations to address the QOD. • Guided inquiry questions during the data collection phase may help students think about the implications of their results. • Some duplication of conditions between students can be desirable to check for reproducibility and reliability of results.
Data Analysis • Students may attempt to address the QOD and their hypothesis from their own data, but eventually a compilation of all data is used to reach final conclusions. • Guided inquiry questions during the data analysis phase can help students uncover the intended relationships and concepts. • Some application of the newly developed concept is undertaken—possibly as a follow-up laboratory experience
The Learning Cycle* • Data Acquisition • What did you do? • Is there any pattern in the data? • What did you find? • What does it mean? • Apply developed concepts • Test hypotheses • Higher level of thinking * Karplus and Thier, A New Look at Elementary School Science, Chicago: Rand McNally (1967); Piaget, Journal of Research in Science Teaching 1964, 2, 176.
Boiling Point Experiment and the Learning Cycle • As a group: • Identify which components (if any) of the experiment correspond to each phase of the Learning Cycle. • Does the boiling point experiment that you worked through follow the Learning Cycle? • [2 min]
Activity 3Is This a POGIL Experiment? • Read through this melting point experiment • Identify whether or not each of the required criteria is met (or is likely met) by this experiment. • Conclude whether or not this is a POGIL experiment • [5 min]
POGIL and SWH:Science Writing Heuristic http://avogadro.chem.iastate.edu/SWH/homepage.htm