There isn't much money left in most 2014-2015 science department budgets. For inexpensive chemistry lab ideas, buy my lab book Chemistry on a Budget for $20.56 at amazon.com or $23 at lulu.com. It will take a few weeks to get to you, so order now!
This book contains 13 labs using consumable materials purchased from local stores. There are two versions of each lab, one with a ten-question conclusion and one with directions for a full lab report. This way the teacher has the option! Each lab is two pages to allow for a single two-sided handout.
My past blog entry on 3/12/15 was about the Electron Dot Diagram (or Lewis Dot Diagram). The blog post titled Lewis Structures & VSEPR Theory on 03/09/14 focused on this concept and moved from the single bonds to a 3-dimensional structure of many bonds.
Today, I am focusing on lab activities and other resources related to VSEPR theory. From the 3/9/14 post:
The lab possibilities are mainly building models of various molecules. Check to see if your department has molecular model kits. To ensure that the kits are returned without pieces missing, you might want to have students sign them out and back in so they take responsibility for the completeness of the kit.
I purchased a set of Styrofoam spheres at a local craft shop (sewing stores might have them as well) for demonstration with toothpicks. I was able to purchase the Styrofoam balls in both larger and smaller sizes, so I was able to use the larger sphere as a central atom and the smaller Styrofoam balls as the attachments.
I've also seen some labs using playdough to attach straws to Styrofoam spheres. If you're so inclined, here's a recipe for homemade playdough:
Here’s a lab based on use of a molecular model kit:
The link below contains 3 pages for a lab building molecular models. It does not specify what is to be used to build the models, so you can use whatever’s available.
The last two pages could be handed out and directions put on the board for students to copy.
There are a few computer-based labs on the Internet. If you have a computer lab or classroom set of computers available, you could use this for a class lesson; or, this could be an Extra Credit opportunity for your students.
The following page could be projected for a class lecture as “real molecules” are shown:
It requires the Java applet to run.
There are several teaching and lab ideas/worksheets lower down on the page.
*This webpage is a favorite of mine because it contains several molecules that are animated and can be explored by students:
I do not use a handout, but simply require the students to neatly record the information from the site for the 12 molecules that are pictured including:
- a "ball & stick" sketch of the molecule
- a statement of the shape
- the number of lone pairs of electrons
- the molecule's polarity
- orbital hybridization
All of this is listed when you click on the molecule.
Here are some other documents about VSEPR theory that you might find useful:
This document contains several pages about Molecular Polarity and Geometry, but you can choose any pages would be useful:
Here is a single sheet with a chart of structures for students to draw/build/practice:
Remember, you can check out the Topic List to help you to find past Blog entries.
Have a good weekend!