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Jump to one of the following molecular shapes' parts:   Choose One Introduction to Molecular Shapes Part 1- Shapes with LiveMath Part 2- Quizzes

For each random quiz that is generated, you will need to determine the Lewis structure, the electron group arrangement, and the bonding group arrangement/shape. The Lewis structure must be determined initially because the theory that we are using to predict molecular shapes, VSEPR, depends on knowing both the total number of electron groups and the total number of bonding groups in the valence shell of the central atom. There are two additional buttons which you can use to better see the shape of the molecule.

The "Animation Window" button will bring up an animated image of the molecule in a new window which will continually rotate the molecule to give you a 360 degree view of it. There is no interaction possible with this image and it's made available for you to give you a bit more information about the shape without requiring you to download any plug-ins for your web browser.

If you aren't running Internet Explorer for Macintosh, the "Chime Window" will bring up an interactive window with the current molecule in it which will let you rotate the molecule and do a number of other things which may help you get a better picture of the molecule's shape. You will need to install a plug-in if you haven't already done so. To get the plug-in, you'll need to head over to MDL Information Systems, Inc and get their Chime browser plug-in (doesn't work in Internet Explorer for Macintosh). They do require you to register with your email address but the plug-in is a free download.

I have more information about the Chime plugin on a separate page.

Important note! The shapes we discuss in class are idealized ones. In other words, "perfect" tetrahedrons, octahedrons, etc. Real life isn't always so perfect and there are factors that affect shape like varying bond lengths and bond angles which I've ignored. When possible, I've used experimental and computational data to make the ball-and-stick pictures and the Chime molecules.

The Periodic Table will always be available on any exam or quiz. Pop up a window if you need to refer to it.

Once you've opened the quiz window for the first time, you don't need to close the window before asking for a new, random structure. All you need to do is switch back to the main quiz window and ask for another quiz. It will appear in the same quiz window as before.