Thursday, October 9, 2014

Pen Display Helps to Make Chemistry Videos for Posting or for Flipping

Using the Wacom 2241 Pen Display in the Chemistry Classroom


One of the main things the attracted me to the iPad in the first place was the way it is a tool for creating short videos demonstrating chemistry problems to be posted online for student viewing and reviewing.  One of the first tasks I completed when I got my first iPad back in 2010 was create a screencast using the ShowMe app that I posted to help my students review Lewis dot structures.  The last time I checked it had over 11,500 views!  (That's a lot for me.)

I started creating chemistry videos back in the early 2000's using an HP tablet.  It took forever.  The software was slow and then the video had to be "rendered" in an appropriate "codec" which could then be posted online as a Quicktime video or Windows Media Player video.  Here are some of my earliest examples that I called Chemistry mini web lectures.  I still use them today and many students have commented that the short videos have helped them understand problem solving.

  

Movie production just got a lot easier and quicker for me!  My department acquired 3 Wacom 2241 pen displays.


The pen display is a large tablet or (22")  extra monitor that can be written on with a special pen.

Saturday, October 4, 2014

Chemistry App Nicely Helps Students See VSEPR Theory

Odyssey VSEPR (Valence Shell Electron Pair Repulsion) app shows molecular shapes


In my General Chemistry class this week we were learning about molecular shapes and VSEPR theory.  The whole point of VSEPR theory is to help us understand the 3-dimensional structure of molecules.  First we learn Lewis dot structures.  Lewis is a helpful theory but we soon see that Lewis structures have many exceptions and they don't really predict shapes.  VSEPR theory is an improvement on Lewis theory in that it does predict 3-D shapes.  The problem is that we then draw these shapes on 2-dimensional paper and the students don't really get a true picture of the 3 dimensions.  The Odyssey folks have created a neat little app that lets us get real close to the 3-D structures on the iPad.  Here is a picture of the app icon:



I have tried other apps that I really like and reviewed in earlier posts.  What is missing from the other apps is a depiction of the unshared or nonbonding electrons that are so important in influencing the shape of the molecule.  In this  Odyssey app the unshared electrons are shown:


In other apps I have used the shape of this bent molecule was clear but Odyssey VSEPR is the only app I have found that shows those two nonbonding pairs of electrons that cause this molecule to be bent.