The kind folks at Wavefunction Inc. have supplied me with their full Odyssey general chemistry app suite and I will be reviewing each of these apps throughout the remainder of summer 2014.
The first app I have chosen to review is the Odyssey VSEPR Theory app (https://itunes.apple.com/ca/app/odyssey-vsepr-theory/id869643629?mt=8), which sells in the app store for $3.99 CAD.
Like many first year general chemistry courses, at VIU our CHEM 140/150 courses cover the concept of VSEPR theory, and how to determine Lewis structure, molecular shape and polarity. These are fundamental concepts which many students struggle with, perhaps due to the 3D nature of molecular shapes or perhaps due to the vector summation required to determine a net dipole moment. To give students experience with these skills, we have included a “dry lab activity” on Bonding and Structure over the past several years. One aspect of this activity is that students are asked to fill out a table (with the formatting shown below) for eight molecules.
Traditionally we bring model kits for the students to play around with, and have copies of the textbook available and opened to the relevant chapter. However, when I saw this app I was immediately excited that we could use it to improve this particular dry lab.
The interface is broken into two portions, an area where molecules are featured for manipulation, and an area that features both a table of generic geometries possible (broken down by the number of lone pairs and electron domains) and a bunch of example molecules.
In the molecule manipulation window, you can rotate the molecules in 3D with a swipe of your finger, or expand/shrink them with a pinch of the thumb and index finger. The molecule can be displayed as wire, ball and wire, tube, ball and spoke and space filling models.
As well, the lone pairs of the central atom and net molecular dipole moment arrow can be added or removed with a single click to each of the right most buttons. The distance between two atoms can be determined by clicking on the ruler, and selecting the distance option, then selecting the atoms of interest.
Similarly, the bond angle between three atoms can also be calculated by clicking on the ruler, and selecting the angle option, then selecting the atoms of interest.
There are questions pre-loaded into the app with multiple choice answers that force the user to work through several of the example molecules.
The responses can be automatically scored in the app, and after trying most of the questions there is the option to view the correct answers.
A glossary is also included, which defines several terms including: axial, dipole, dipole moment, equatorial, ligand, lone pair and VSEPR.
Although the app is limited to the “canned examples” included, there are a decent amount and they certainly cover the fundamentals explored in a typical discussion of VSEPR at the first year general chemistry level. I plan to use this app in the fall semester to highlight the 3D nature of molecular shape in my CHEM 140 lecture by hooking up my ipad mini to the project. If we are able to scrounge up a class set of ipads, I could see this replacing or enhancing the current pen-to-paper method used in the dry lab.
The author received an evaluation copy of the software from Wavefunction Inc, but received no other compensation.