In this activity, students self-organize according to periodic trends. I print out the attached cards onto card stock (each page will contain two) and hand them out to the students (one to each). Generally, we go outside and I shout out periodic trends (i.e. size, polarizability, ionization energy, Zeff etc.) and the students run to get in line in the correct order. I have a bell which I ding if correct, and a buzzer that I sound if incorrect. If incorrect, they have to try again. Students can "shout out" to their peers suggestions as to the ordering. After the students are in the correct order (and sometimes when they are in the incorrect order if I see a consistent misconception in their thinking) I ask at least one student the reason for their chosen ordering. The "Instructor Notes" describe how I use this activity in General and Inorganic Chemistry and include a discussion of some common student misconceptions.
This activity typically takes about 10-15 minutes at the end of the lecture period in which we review periodic trends. It can be easily modified for classes of different sizes by adding more atoms and ions.
A student should be able to apply his/her knowledge of periodic trends to participate in ordering a list of atoms and ions according to a given trend and should be able to explain the reasoning behind her/his choices.
The attached atom cards printed on card stock as well as a buzzer and a bell (or two other sound making devices).
The students really like this! Especially if they get to go outside (though running up and down the chemistry hallway is fun, too)!