POLYATOMIC CATIONS AND ANIONS

Following are several videos that explain polyatomic ions:

1. http://www.youtube.com/watch?v=oSP_7AS5mRE

2. http://videos.howstuffworks.com/hsw/22643-compounds-polyatomic-ions-video.htm

This video shows an interesting and creative way to remember the polytomic atoms:

http://www.wimp.com/polyatomicions/