Ever wonder why some call precipitation reactions "double decomposition". Perhaps (or perhaps not) two (double) salts are sort of splitting apart (decomposing?) and then reforming with other radicals. But a solvent (usually water) is necessary to achieve the desired effect. But is adding water to a salt really decomposition?
This post describes some simple experiments using various coins and neodymium magnets that connect to the 2019 National Chemistry Week theme of Marvelous Metals!
If you look at any chemistry textbook, you will see Lewis structures introduced long before electronic and molecular geometries. This makes sense since you need Lewis structures to determine molecular geometry. Unfortunately, research has shown that students often do not recognize that the purpose of drawing Lewis structures is not to create the structure itself but to use it as tool to understand the properties of the molecule (Cooper, Grove, Underwood & Klymkowsky, 2010).
An advantage to teaching on the trimester schedule allows me the opportunity to teach the same course again roughly twelve weeks later. So after grading my 2nd trimester students’ Chemistry B final exams, I was able to evaluate certain topics that caused my students problems, reflect on my teaching, and then determine how I was going to better prepare my students in the 3rd trimester chemistry B class.
Wow! A very neat experiment, called “Hydroglyphics”, published by Kim, Alvarenga, Aizenberg, and Sleeper in the Journal of Chemical Education allows you to transform a common plastic Petri dish into a unique teaching tool to demonstrate the difference between hydrophobic and hydrophilic surfaces. Check it out in the video.
