<!--[if !supportLists]--> I. <!--[endif]-->Teaching Idea # 1: Analogy for Orbital around the Nucleus.
<!--[if !supportLists]-->· <!--[endif]-->Content Area : Chemistry
<!--[if !supportLists]-->· <!--[endif]-->Grade Level: 10th Grade
<!--[if !supportLists]-->· <!--[endif]-->Source : Ngoh K. Goh, Lian S. Chia, Daniel Tan(1994).Some analogies for teaching atomic structure at the high school level. Journal of Chemical Education-ACS publications Volume 71(7) 733-734.
<!--[if !supportLists]-->· <!--[endif]-->Required materials: None.
<!--[if !supportLists]-->v <!--[endif]-->Description:
A classroom and the probability of a student being present in that particular classroom are used as an analogy for orbital around the nucleus. The teacher explains the concept of orbital to the students by letting them to resemble the area of the classroom to the area of the orbital where electrons can be present as the students are present in that area of the classroom. Also the teacher leads them to resemble the probability of the student present or absent in this area to the probability that an electron is present in the orbital or not. The exact place where the students sit in the classroom is resembled to that specific point within the orbital.
<!--[if !supportLists]-->v <!--[endif]-->Use and Purpose:
Explaining the concept of orbital using this analogy, reduced the chances of common misconception that the orbital are separate circles drawn around the nucleus. Also it doesn’t let the students to think like there are spaces between the imaginary orbital. In this way the students understand the orbital as an area around the nucleus in which there is a certain probability that an electron is present or not.
<!--[if !supportLists]-->v <!--[endif]--> Ways to adapt to different situations:
In addition to the idea of the orbit, this analogy can be used later to explain the process by which the atom losses electrons. That is by explaining that the students who are placed near the boundaries of the classroom are more likely to leave the area of the classroom than those who are sitting in the middle. In this way the teacher may explain that the electrons, which are located at positions near the edges of the orbital (the valence electrons on the last energy level), are more likely to be lost that those electrons that are at the middle (near the nucleus). Therefore, this analogy can be used to explain the concept of valence and valence electrons of the atom.
<!--[if !supportLists]--> II. <!--[endif]-->Teaching Idea # 2: The Spatial Feature of the Atom.
<!--[if !supportLists]-->· <!--[endif]-->Content Area : Chemistry
<!--[if !supportLists]-->· <!--[endif]-->Grade Level: 10th Grade
<!--[if !supportLists]-->· <!--[endif]-->Source : “ Nova Elements” “Explore the interactive Periodic table” http://www.teachersdomain.org/browse/?fq_hierarchy=k12.sci.phys.matter.atom
<!--[if !supportLists]-->· <!--[endif]-->Required Materials: Computer and projector.
<!--[if !supportLists]-->v <!--[endif]-->Description:
The interactive periodic table is very useful for the students to make an image of an atom considering the difficulty of the students in imagining something that they have never seen. The teacher clicks on any element on the interactive periodic table and asks to “build” that atom. A new page of that particular element opens where the atomic mass and the atomic number of that element are mentioned, plus data about the element is given. Here, the teacher can add or remove protons, neutrons and electrons by clicking on their corresponding bottoms till it reaches the number of protons mentioned. Every time the teacher adds or removes a proton the name of the element changes and the size og the electron cloud or the nucleus changes. The teacher and the students may add or remove protons, neutrons and electrons till they build the atom of the chosen element.
<!--[if !supportLists]-->v <!--[endif]-->Use and Purpose:
Using this interactive periodic table, the students will be able to learn and distinguish the location of protons, neutrons and electrons because as they click on the proton or neutron bottoms these particles are placed in the nucleus, while as they click on the electron bottom the electrons are placed at the orbital. In addition to this, the chance of misunderstanding that the atoms are flat rather than spatial will be reduced because as the electrons are added, they begin to rotate around the nucleus in a very interesting way and give a three dimensional image.
<!--[if !supportLists]-->v <!--[endif]--> Ways to adapt to different situations:
This interactive periodic table may be used latter to introduce the concept of ions and isotopes. As the students add more protons than electrons, the atom will become a Cation (positively charged ion) and as they add more electrons that protons the atom will become an anion (negatively charged ion). As the students change the number of the neutrons keeping the number of protons constant, they will notice a change in the atomic mass. They will be able to compare atoms of same proton number but different atomic masses and build the concept of Isotopes.
<!--[if !supportLists]--> III. <!--[endif]-->Teaching Idea # 3: Basics
<!--[if !supportLists]-->· <!--[endif]-->Content Area : Chemistry
<!--[if !supportLists]-->· <!--[endif]-->Grade Level: Grade 7
A video of 1.57 seconds.
<!--[if !supportLists]-->· <!--[endif]-->Required Materials: Computer and projector
<!--[if !supportLists]-->v <!--[endif]-->Description:
This video gives a simple explanation about the structure of the atom. It doesn’t enter into the details of the structure but it gives a model of what the matters are consist of. It explains the subatomic arrangement and their differences in charge and size. It also shows why the electrons don’t separate from the atom as they move rapidly around the nucleus. At the end, it gives examples of hydrogen, oxygen and iron atoms.
<!--[if !supportLists]-->v <!--[endif]-->Use and Purpose:
This video can compensate the ordinary pictures found in the textbooks. It is preferable because it gives a three dimensional images and explains the movements which is a feature that the ordinary pictures lack. This helps the students to overcome many misconceptions. For example, after watching this video there is little chance for the students to think that the electrons are located at one place on an orbital without moving. Also they will never think of the empy spaces found between the electrons.
<!--[if !supportLists]-->v <!--[endif]--> Ways to adapt to different situations:
This video may be continued to go little bit more in details, after which it can be used in higher grade levels. For example, the notion of the isotope can be established as the video shows the same element with different neutron numbers. Additionally, the concept of energy levels can be introduced, not to present all the electrons as if they have equal strengths. Also, the idea of molecule formation can be introduced by showing images of how the atoms share electrons and make up covalent bonds.
<!--[if !supportLists]--> IV. <!--[endif]-->Teaching Idea # 4: Resembling an Atom to Solar System
<!--[if !supportLists]-->· <!--[endif]-->Content Area : Chemistry
<!--[if !supportLists]-->· <!--[endif]-->Grade Level: Grade 7
<!--[if !supportLists]-->1. <!--[endif]-->Source : Keith Taber, (2002). Chemical misconceptions- prevention, diagnosis and cure. Volume 1: theoretical background, 112-115
<!--[if !supportLists]-->v <!--[endif]-->Description:
This is an analogy that is used by lots of teachers as I noticed on the web and also in this book. The teachers explain the structure of an atom by resembling it to the solar system. The sun, located in the middle, is conformed to the nucleus and the planets that rotate around sun at different distances represent the electrons that are not attracted to each other but the sun. Both, the solar system and the atom, have forces involved in the attraction of the center to the orbital. In addition to these similarities, the differences between these concepts are given to avoid misconceptions.
<!--[if !supportLists]-->v <!--[endif]-->Use and Purpose:
Using this analogy is a way of teaching the students the structure of the atom byr resembling the atom to the solar system that they already know about. It serves as a bridge between the new knowledge to the one before. Since the students are more familiar to the solar system than to the atom, it is easier to compare the similarities and the differences between the solar system and the atom. In this way an abstract idea that is impossible to be seen by the students in converted to an image that is visible and familiar.
<!--[if !supportLists]-->v <!--[endif]--> Ways to adapt to different situations:
This analogy can be further used in explaining the forces of interaction in the higher level of education. The
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