(Note: I apologize for the formatting. I used Word's bullet system, but the spacing doesn't transfer, much to my chagrin!)

  • No problem... but you should have gone back and fixed it later. duh.
  • - fogleman fogleman

Title: Distributing Electrons – Electron configuration

Grade Level: 10th-12th

Lesson Overview: Students learn how electrons are ordered into subshells and orbitals in molecules. A teacher led demonstration makes a clear display of the hidden order of how electron configuration might appear. After this, there will be a small lecture on how to represent electron configuration in writing. Students will then break into groups and be given a worksheet to complete for homework.

Learning Outcomes:
a. Learning Performances
i. With the completion of the lesson, students will be able to predict the electron configuration of novel elements. They will also be able to describe the idea of orbitals, and how the electrons fill these orbitals in 3D for the s and p orbitals.
b. Links to standards
i. C4.8x Electron Configuration – Electrons are arranged in main energy levels with sublevels that specify particular shapes and geometry. Orbitals represent a region of space in which an electron may be found with a high level of probability. Each defined orbital can hold two electrons, each with a specific spin orientation. The specific assignment of an electron to an orbital is determined by a set of 4 quantum numbers. Each element and, therefore, each position in the periodic table is defined by a unique set of quantum numbers.
1. C4.8e Write the complete electron configuration of elements in the first four rows of the periodic table
2. C4.8f Write kernel structures for main group elements

Students’ Prior Knowledge of Experiences: Students will need to have basic understanding of molecular structure, and familiarity with the some quantum theory may be helpful, but is not expected. As for students’ misconceptions regarding the distributions of electrons, these may include the notion that electrons travel around the nucleus much like planets in orbit around the sun. This stems from common representations in textbooks that depict simple models, but do not fully explain the concept of a shell or cloud of electrons.

Establishing Purpose: The purpose in the lesson is to provide students with a basic understanding of the visual concept of electron configuration, as well as the way that chemists have labeled and defined these orbitals in order to discuss elements. Later, this is used in Lewis dot structures and orbitals, determining valence electrons, and ultimately, patterns for bonding. The motivation for students will be come from the demonstration in which they will see electron configuration in a working model.

  • This topic seems difficult to relate to the Ss world. Is there a way to introduce a descrepent event, i.e. you though electrons were like this but that doesn't match how we seem them behave, etc.?
  • - fogleman fogleman

Instructional Strategies: The small “pair and share” will help students with recognizing misconceptions and other ways of thinking about the issue. Also, the demonstration should help with attention, and hopefully draw out student interest for the subject material.

Materials Needed:
a. Two-dimensional working model of Neon electron configuration demo: Using a plastic bowl wrapped 50+ times with copper wire and filled with water, use small corks that have magnets attached to the bottom. Then, attach a voltmeter to either end of the wire and use the corks as “electrons” and observe how they arrange themselves in the bowl. Optionally, using a mirror to reflect the surface towards the students could be useful, but is not required. This is a working model, and each cork will be placed in a one at a time in order to hopefully stir student interest. Since the corks will arrange themselves in a geometric shape with each new one, students should see that there is an order for how the corks space themselves, even though they don't appear to have a reason to. When all ten electrons are in place, it displays the first two levels of the inner core of the neon configuration (although this is still limited as its merely two dimensional, which will be discussed later).

  • I think you will need magnet work for this to work. Magnet wire looks like uninsulated wire, but is actually coated so that each turn is a separate current carrier. More importantly, you will need a high current power supply. The physics teacher may have one. Be sure that it is protected somehow (fuse or breaker) so that you don't short it. Are there misconceptions that this demo might encourage?
  • - fogleman fogleman

Time Required: 50 min class period

Instructional Sequence:

a. Introducing the lesson
i. Begin with a short “pair and share” of students’ ideas of how electrons behave. Students will work independently at first writing down some initial thoughts, and then in pairs discuss each other’s ideas and between the two come up with the best explanation. After this, each pair will share their ideas with the class. The purpose is to draw out misconceptions as well as activate their prior knowledge for atoms and electrons. Because they are sharing between themselves, this will hopefully encourage an atmopshere of sharing viewpoints and prior knowlege to hopefully construct basic models between groups, and then again in the larger classroom. I plan on gathering these ideas, but not exactly dispelling them until later. With this information, I hope to lead into the demonstration, which may challenge some ideas and support others.

  • Will you ask students how they know about how they think electrons behave?
  • - fogleman fogleman

b. Body of Lesson
i. The teacher-led opportunities for this lesson will be the demonstration (not only performing the demo but also the reflection of the major ideas that the demonstration represents). Also, I will need to facilitate the "pair and share" discussion. Lastly, after the demonstration is complete, a small lecture will be required in order to relate the way to determine an element's electron configuration. Its important for students to see how this can be determined using the periodic table. The important aspect of the talk is to solidify what was discussed in the "pair and share" as well as the observations of the demonstration into describing this phenomenon scientifically. Another major point to stress will be the process in determining electron configuration, as this is what will help them remember many other aspects of later chemistry.

  • You should be more specfic about the sequence of the demo, questions, etc. Look at Ethan's lesson plan for ideas.
  • - fogleman fogleman

ii. Possible questions for prompting student thinking during lecture: When you visualize an atom, what does it look like? What do you think the heavier elements look like with so many electrons? What effect do electrons closer to the nucleus have on electrons that are farther away? Why is the demonstration model limit what we know about electrons? Perhaps other questions as well, but the aim for these will be to test for higher order thinking skills. Also, questions that probe student understanding of the material will help to provide in-class assessment. For example, where do we find the s,p,d,f blocks? Another way to assess students is to model an example and ask different, specific students to fill in the next step.
iii. Links for the lesson can be seen in the preceding lessons where students utilize their knowledge of electron configuration and valence electrons to describe molecular geometry and bonding.
c. Concluding the Lesson
i. The lesson will end with work on the worksheet (time permitting). The worksheet will cover many different examples of elements, and how to determine their electron configuration using the periodic table. Beyond the examples of elements, there will be a few analysis questions that expand on some parts that relate to prior lessons. Also, at the top of the sheet I may also had a small "how-to" model reminder for students in order to scaffold the method for determing electron configuration.

Assessing Student Understanding:
a. Student understanding will be assessed using the worksheet as homework, and also with a quiz that covers this material as well as the next few following lessons. The quiz will use new examples of electron configuration (alongside more material than what is covered in this lesson).

Student Resources:
a. No other materials are needed except the notes taken from lecture as well as the worksheet. (Assuming they have already been given a periodic table in some form)

a. Safety issues with the lesson may result from the exposed ends of the voltmeter. Address this issue if students are permitted to view the bowl up close. Also, setting up this demo beforehand and testing it’s reliability should also be done in order to make things smoother within the allotted class time.

Lesson Rationale
[[Comments on Erics Demo Lesson|]]