15 Jul 2014

Examining and Drawing Atomic Orbitals

Lab Experiment

Submitted by Christopher Goh, Williams College
Categories
Corequisites: 
Prerequisites: 
Course Level: 
Description: 

This exercise makes use of a web-based tool to review quantum numbers of the orbitals of the hydrogen atom and to visualize atomic orbitals in 3D. Students are asked to draw the 1s-, 2p- and 3d-orbitals.

AttachmentSize
File Atomic Orbital Worksheet224.29 KB
Learning Goals: 

The student should be able to 

  • identify atomic orbitals by their quantum numbers and by their letter labels.
  • describe and draw the 3D shape of a 1s-, 2p- and 3d-orbital (showing only angular nodes)
  • have an appreciation of the spatial orientation and 3D nature of these atomic orbitals
Equipment needs: 

3D Glasses enhance the students' perception of the 3D nature of the orbitals. The glasses are available for <$20 per 50 glasses from your favorite online retailer.

Access to the web.

Implementation Notes: 

Prior to this activity, students were introduced to atomic orbitals in lecture (of a first-semester introductory general chemistry class). The organization of the class and associated lab was such that I was able to run this exercise as an "in-lab" activity (to complement a lab discussion) for lab sections of up to 16 students. The lab sections met in a classroom with a computer for each student.

After a brief overview (and handing out the 3D glasses), I took students through navigating the web resource up to the 1s orbital. The remaining exercises the students completed at their own pace. In designing this exercise, I wanted to set the time aside for students to appreciate the spatial nature of atomic orbitals - the "Dotted Model" in particular led to the most numbers of comments from the students. Reactions to drawing out the orbitals was mixed. A handful of students claimed not to be artistic enough to draw the orbitals (they managed just fine); most enjoyed the 3D visualization.

 

Time Required: 
45 minutes
Evaluation
Evaluation Methods: 

I collected the worksheets to ensure that students completed the exercises. Worksheets were graded for correctness and completeness and received a small bonus for extra efforts.

 

Evaluation Results: 

With all the answer provided on the web site, nearly all students completed the worksheet correctly.  Few students took short-cuts and attempted to rush through the exercises with a minimum of attention. For most part, students took the time to work through each step of the exercises and to generate diagrams to the best of their abilities. Quite a few students produced beautifully drawn orbitals with spatial perspectives.

Creative Commons License: 
Creative Commons Licence

Comments

The Web Resources link and the embedded link in the attachment need revision: Point to

http://csi.chemie.tu-darmstadt.de/ak/immel/

and select the "Tutorials" tab to get to the correct page

The VIPEr community supports respectful and voluntary sharing. Click here for a description of our default Creative Commons license.