Katie WalkerPHY 690Draft 1Abstract: This paper focuses on the conceptualization of the Bohr Model of the atom while simultaneously fulfilling the New York State Regents requirements; via the Arizona State Modeling Curriculum and research, online simulations using the website PhET.colorado.edu\, and the website of St. Mary’s school in Manhasset, NY; www.stmary.ws/highschool/physics/.The foundation of these applications have been extracted from Arnold B. Arons’ Teaching Introductory Physics, The PhET: Design Process; Look and Feel, and New YorkState Standard 4, Key Idea 5 and Performance Indicators 5.3a; 5.3c and Process Skills 5.3i and 5.3ii.When introducing students to the idea of quantized energy levels, it is important to stress the qualitative nature of the atom prior to any quantitative work. Using the Bohr Model simulation on www.stmary.ws/highschool/physics/home/notes/modPhysics, students are able to view labeled packets of energy interacting with electrons occupying discrete energy levels. This simulation allows students to see that the electrons occupyingthe energy levels require a precise amount of energy to jump to the next level.1 Once that idea is understood, it is important to begin to develop the idea that all elements have unique energy levels that require unique energies in order to allow electrons to jump to outer energy levels. For example, helium and carbon have four energy levels, Lithium and Hydrogen, five and Sodium six.Once students have began to conceptualize the idea that each element has a uniqueset of discrete energy levels, the emission of photons can be explored. The photoelectric effect is not required of the New York State Board of Regents; however, investigation into Einstein’s Nobel prize winning idea provides a strong foundational understanding of not only spectral lines associated with the Bohr Model, but also farther insights supporting ideas in modern physics that students will encounter in higher level courses. 1 The St. Mary’s Physics website offers comprehensive and interactive notes and simulations that can be used by teachers for in class discussion, then referenced by students outside of class. There are a variety of instructional approaches for each topic; while fulfilling all New York State Regents requirements.This website is especially helpful when discussing more complex or abstract topics such as quantized energy.“ Its intelligibility to students provides a rational step to modern insights. “ (Arons, 300)When discussing the absorption and emission spectrum of common elements, the St. Mary’s physics website is a useful visual tool for students. The Black Box and AtomicSpectra simulations not only provide a visual example of emission and absorption spectrum for all elements, but simultaneously stress that each energy level transition that produces a single spectral line. In addition, it is emphasized that in absorption, electrons are elevated from ground state to higher states and those transitions produce spectral lines, while the emission spectrum results from electrons cascading down through intermediate states and also directly to the ground state. The students can directly view the results of the simulation, additional lines from emission.To further ensure the connection between exclusive energy levels and spectral line production students should draw energy level diagrams similar to the Hydrogen energy level diagram in the New York State Regents Physics Reference Table for various differentelements. “..need to expose students to such qualitative questions from the earliest encounter. “ (Arons, 299) When the Bohr Model of the atom is introduced qualitatively, quantitative relationships become more apparent to the students. The equation E = hc/ is more meaningful; students are able to see the purpose behind calculations. Students also understand why energy levels are subtracted in order to determine the number of electron volts necessary to move to the next orbit; and how they can determine the number of emission and absorption lines. In addition to utilizing the St. Mary’s Physics website, there are several other methods that can be used to aid students’ conceptualization of the Bohr Model and corresponding spectral lines. The University of Colorado has a website of science simulations, including one specifically addressing photon emission and absorption and comparing the evolving models of the atom. (Physics Teacher, February 2007)2 Walter Fendt’s applet “ is useful for selecting quantum numbers and comparing wave and particlemodels. ” (Physics Teacher, February 2007)3 Computer simulations allow for a more personal dialogue between the instructor and the student that is not possible in the typical high school classroom. If an effective dialogue is written by the instructor, the student can achieve the same benefits while working independently. (Arons, 370) Whole group classroom demonstrations are also significant review or introductionmethods while analyzing the Bohr Model of the atom. Jay M. Pasachoff of Williams College had a Bohr Staircase constructed by two carpenters for use in his classroom. Thesteps of the staircase are proportionally spaced to the Hydrogen energy levels. He introduces the Lyman and Balmer series prior to any calculation, to emphasize conceptualization rather than the meaningless “plug and chug” method. (Physics Teacher,January, 2004)2 www.colorado.edu/physics/2000/quantum-zone/bohr.html3 www.walter-fendt.de/ph14e/bohrh.htmWhen teaching the Bohr Model of the atom in a high school physics class, it is imperative to mind how the Bohr Model impacted the current development of quantum physics. Although Bohr’s model was determined to be flawed, his concepts were unprecedented in the study of the physical world. As a high school teacher, it is importantto teach students the required content, but also prepare them for future study in physics; and provide them with knowledge of modern thought. Teaching beyond the New York State requirements offers students a more broad and comprehensive view of current physics topics. Differing presentation methods to students is helpful in bridging the gap between common misconception and accurate analysis. Methods such as interactive notes, simulations, lecture, practice problems and classroom demonstration can be effective and enjoyable tools to successfully help students conceptualize the mathematics involved
View Full Document
Unlocking...