ISSN: 2455-6203 International Journal of Science Management & Engineering Research (IJSMER) Volume 01: Issue 05: |October 2016 www.ejournal.rems.co.in Study and Evaluation of Quantum Atomic Physics Kalpana Vishwakarma, Mohit Shrivastava , SBS Academy Indore Teaching Methodology The teaching approach under consideration has been under development for about ten years. Basic ideas are: (1) From Bohr to Schrödinger A modern representation of atomic physics using the Schrödinger equation as a theoretical basis. The main focus here is on qualitative understanding and interpretation of the y-function, not on mathematical capabilities. (2) Reducing the mathematical demands We use the analogy of the standing wave in order to introduce the basic concept of a state (n, Wn, yn).In addition, the computer is used for modeling the Schrödinger equation for many special cases like hydrogen atom, higher order atoms (He, Li) and molecules. (3) Relating measurement to theory in a variety of phenomena. Our approach is directed to the development of applications of our quantum model to a wide range of phenomena in atomic physics, chemistry and solid-state physics. (4) Student Orientation The process of conceptualization and learning of students is to be specifically promoted by studentoriented phases at the beginning of each new chapter. The investigation reported here had the aim to use this new concept in normal school teaching with three voluntary teachers, who had to be trained with this approach before. The chapters of this script are: Light and electron as quanta; classical standing waves; the hydrogen atom; higher order atoms. THE EVALUATION CONCEPT Research questions of the evaluation study 1. How far are students achieving the objectives related to this new approach? Do they develop a deeper understanding of atomic physics as it is defined by this teaching approach? 2. How are conceptions and understanding of students changed during instruction? Design Data were gathered from questionnaires before and after teaching, from interviews after teaching, IJSMER201632 and from observations during teaching. There were altogether 26 students in three classes. Knowledge domains Coming from our basic ideas as stated above, we defined the basic knowledge domains from the main contents of our manuscript. As the basis for the evaluation, we defined six knowledge domains of the approach: Atom This objective means that students should develop a description of atoms using an orbital model. Some special aspects of this tested by specific questions of the questionnaire are: Use of a consistent description in different situations; use of physics concepts (such as charge cloud, probability density, state, etc.) to describe an atom; an understanding of the model character of these descriptions; to be able to distinguish different models of the atom. y -function This objective is related to an understanding of the y-function and its interpretation. Special objectives are: To draw y-functions in different states; interpretation of the y-function with the notion of charge distribution or probability density distribution; to connect the y-function of an atom with the notion of a state. Notion of state This objective is related to an understanding of the concept of state. Special objectives are: To connect the concept of state with special physical variables which are characterized by the state (energy distribution); use of the concept of state to describe the model of an atom; to explain processes like emission and absorption using the concept of state. Schrödinger equation (SEq) This objective is related to a theoretical understanding of the use of the Schrödinger equation to describe atoms. Special objectives are: List and explain the variables in the Schrödinger equation; describe processes to solve the 188 | P a g e ISSN: 2455-6203 International Journal of Science Management & Engineering Research (IJSMER) Volume 01: Issue 05: |October 2016 Schrödinger equation in a special case; to be able to explain properties of solutions; to explain the form (curvature) of a y-function by using the Schrödinger equation and especially the variables of energy and potential in it. Relating measurement to theory This objective is related to the understanding of relations between theoretical results from the Schrödinger equation and corresponding results of measurements. Special objectives are: To connect differences in energy level diagrams and frequencies of light spectra; to connect the form of a y-function (and a theoretical definition of the radius of an atom) with measurement of size of an atom. Higher order atoms This objective is related to students' ability to understand, how higher order atoms with more than one electron can be described and modeled with the Schrödinger equation. Special objectives are: To understand the shielding effect of electrons on the potential; to understand the combination of states in higher order atoms; to understand the use of the Schrödinger equation for each single electron and their interrelation; to distinguish the state of an electron and the state of an atom. Questionnaire From this content structure, we developed our questionnaire with mainly open ended questions and a final interview with all 27 students. Selected questions of the questionnaire Draw a picture of an atom and label it! Describe your model with a few sentences. Can you determine the size of an atom in your model of an atom? Given three drawings. Describe commonalties and differences between these three atomic models and use the notions "electron orbit", "probability density", and "charge cloud". Performance levels In order to define performance levels for all six knowledge domains, we had to find out combinations of different answers to different questions related to these knowledge domains. Because of the open-ended nature of questions a IJSMER201632 www.ejournal.rems.co.in student could answer with his knowledge to one question or another, and we had to take into account the different answers to different questions related to the same knowledge domain. So, item combinations were defined to determine performance levels. These item combinations were determined by logical analysis of the answers in relation to our knowledge domains and justified by correlation between different item combinations. By this method we got the following three performance levels for all six knowledge domains Level Description 2 The combinations of students' answers were along the expectations from our teaching approach. 1 The combinations of students' answers showed some major deficiencies. 0 Students' answers were weak in relation to the expectations from our teaching approach. RESULTS Results about performance levels The results for the three performance levels in all six knowledge domains (research question 1) are displayed in figure 1. Good results in the domain "atom" tell us, that most students have gained a good or moderate understanding of the orbital model. In the domain "y-function" a qualitative understanding of the Schrödinger equation (details see above) was gained to some extent. Some students did very well, but most of the students had some deficiencies. The knowledge in the domain "notion of state" turned out to be the second best, so many students got a good or rather good understanding of the notion of state and its importance for explaining phenomena of size and light spectra. In spite of some efforts of our approach to foster a qualitative understanding of the Schrödinger equation (domain "Schrödinger equation (SEq.)"), and work with it in graphical computer models, the understanding here of most students was on a rather low level. 189 | P a g e ISSN: 2455-6203 International Journal of Science Management & Engineering Research (IJSMER) Volume 01: Issue 05: |October 2016 Figure 1: Number of students in three performance levels 0, 1 and 2 of six knowledge domains (atom, y-function, notion of state, Schrödinger equation (SEq), relating measurement to theory (T+E), higher order atoms (h.A.) Knowledge domain "relating measurement to theory"(T+E) In this content domain we analyze students' ability to relate theoretical models and experimental observations and measurements. From students' responses to various items of the questionnaire we analyze whether experimental observations can be explained with the intended atomic model. The items are divided in two groups: Measurement of spectra related to the changing energy of atoms and items where students tell something about the size and radius of atoms. The results in figure 1 show, that students did rather well in this - from the view point of our approach - important knowledge domain. Higher order atoms This also was an important part of our approach. But most teachers had not enough time for this chapter, so the low results were not so surprising. Results about different classes In addition we show differences between the three classes in figure 2. IJSMER201632 www.ejournal.rems.co.in Figure 2: Performance levels 0, 1 and 2 of six knowledge domains (atom, y- function, notion of state, Schrödinger equation (SEq), relating measurement to theory (T+E), higher order atoms (h.A.) in three different classes Students in class H have achieved better results than in the two other classes. From our observations of the classes there are several preconditions that have influenced the outcome. The teachers differed in their acceptance of our approach and in their physics background. Half of the students in class W were not native German speakers. In average the students in class H spent more time for preparations and reading the text book than students in classes W and V. Despite these preconditions the results in each class for its own are quite similar; students have achieved a better understanding of the objectives atom, Psi and state compared to the objective SEq. The levels on the vertical axis might be translated as 2.0 is excellent; 1.5 is very good; 1.0 is sufficient; 0.5 means students have achieved a preliminary understanding, and 0.0 means that they have got nothing out from the course. The values on the vertical axis are mean values of all students in one course. With respect to the objective "atomic model" students in class H have achieved very good results, whereas students in the two other classes have achieved only average or less results. With respect to the objective "y-function", students in the classes H and V have achieved average results, whereas in course W they have only reached a sufficient level on average. With 190 | P a g e ISSN: 2455-6203 International Journal of Science Management & Engineering Research (IJSMER) Volume 01: Issue 05: |October 2016 respect to the concept of state, students in course H have achieved very good results, whereas in the classes V and W they have only achieved sufficient level. The knowledge achieved about the mathematical understanding of the Schrödinger equation gets the lowest scores in all three classes. The average even in class H is less than 1.0, so this means that a mathematical understanding was not developed to a high level. One of the most important objectives for our approach was to enable students to see a connection between results of theoretical modeling and results from measurements, such as size of the atoms or frequency of spectral lights. The results show that this aim was achieved to a good average level in course H and course V, whereas the average level of students in course W was only sufficient. The aim to understand the modeling of higher order atoms with more than one electron was achieved to a good average level in class H, the other classes got lower results, but we know from observing the teaching that the teachers in these classes gave only little time to this part of the instruction. Results about students changes in conceptions from pre to post questionnaire www.ejournal.rems.co.in 3. More than 20 students change from an electron orbit view of electrons in an atom to a charge view. Nearly all students develop a good notion of an electron distribution. Nearly 45 % of the students develop some good notion of a state and abandon a description of electrons which includes the notion of motion. CONCLUSION A new approach to teach quantum atomic physics in upper high school has been transmitted to three teachers of ordinary high school with partial success. In one of the three classes all but one objective have been reached by many students. Only the mathematical understanding of the Schrödinger equation got less average level than 1.0. In two other classes some of the objectives also have been reached with good success, for instance achieving a new atomic model or understanding some relations between theoretical model and results of measurement. Other objectives failed to reach a sufficient level. We conclude from these results that although it was not possible for most of the students to develop a deeper understanding of the theoretical description they achieved an average to good understanding of the basic quantum mechanical concepts. REFERENCES [1] A learning pathway in high-school level quantum atomic physics. Int. J. Sci. Educ., Vol. 20, No. 9, 1075-1088 Niedderer, H., Bethge, T., Cassens, H., Petri, J. [2] Teaching quantum atomic physics in college and research results about a learning pathway. In. E. F. Redish, J. S. Rigden (Eds.). Figure 3: Changes in conceptions from pre to post questionnaire Some results about students' conceptions (research question 2) related to electron orbits, electron cloud, concept of state, concept of shell, distribution and movement and their change from the pre test to the post test are displayed in figure IJSMER201632 [3] The changing role of physics departments in modern universities, Proceedings of the International Conference on Undergraduate Physics Education (ICUPE). New York: American Institute of Physics, P.659-668 191 | P a g e