In this activity, Introductory Chemistry students are given two possible structures of sulfur dioxide, and based on an assessment of given vibrational modes, they determine which of the modes are IR active (and thus, whether the molecule is a greenhouse gas).  They compare their assessment to experimental IR absorption peaks, and the students decide which structure is valid.

I like having students look at data and then explain data based on what they know about periodic trends. This activity uses the data we all use for radii and ionization energies and asks students to look just a little bit deeper. 

I have gone back and forth between using this as an in class activity (my current practice) and using some of these questions on exams. 

Late in their junior year and into the first two months of their senior year, chemistry majors at Willamette write and submit a research proposal.  Shortly before entering the lab for their thesis work, I lead this activity that takes place in our Senior Projects seminar class.  The class meets one hour per week and we cover topics such as how to write an effective grant proposal, ethics in science, presenting data, etc., as well as this safety activity.

This spoof of the song "Isn't It Ironic" (by Alanis Morissette) summarizes the properties of ionic compounds in verse. Suitable for General Chemistry classes as well as Inorganic Chemistry, although a reference is made to the Born-Meyer equation.