Before class on Nov. 30:

• Watch the 3 videos below(14 min, and 14 min and 12 min );
• Make a comment.

Before class on Nov. 28, please watch the following videos. I did not make these videos, but I think the instructor uses computer animation and analogies in a way that is very helpful.  There are 6 videos, and each video is 4 minutes or less, so you have in total between 22 and 24 minutes of videos.

These videos define lattice energy as the energy required to break apart an ionic formula into separate, infinitely spaced gaseous ions.  WE  are defining lattice energy in the OPPOSITE way– as the energy released when two gaseous ions come together.  So our lattice energies will be exothermic, or negative.  However, everything else about thee videos applies.

Also, here is the answer key for the

Lattice Energy Worksheet.  Be prepared to discuss on Monday.