Back to school time means back to lab time too. Students new to chemistry have a lot on their plates the first few labs—learning unfamiliar safety procedures, becoming accustomed to writing lab reports, even figuring out which glassware they’re looking for in their lab space. How can teachers help them to navigate this newness? Two articles in the July 2016 issue of the Journal of Chemical Education are useful resources for “back to lab” time.
It all started with a class my son and I took together at Marc Adams School of Woodworking (link is external). To make a long story short, we started on a Saturday morning with nothing and left Sunday afternoon with a custom built longboard. (Think skateboard but...well...longer).
Previously I wrote about taking part in a district-wide high school blended learning pilot. You can read about it here. I received my Chromebook cart near the end of February/beginning of March. A little late but just in time for the periodicity unit I was planning as a blended unit. The following is a breakdown of how I designed the unit.
In the lab, students are given a 1.5 gram samples of copper. The copper is taken through a series of five chemical reactions ending with the precipitation of solid copper. After the five reactions, students are asked to return their 1.5 gram samples of copper to the teacher.
It is really hard to get to know THAT kid especially when I have classes of other kids who are important and have needs also. Stack on top of this teenage hormones, spring, nice weather, prom, AP tests, state testing and trying to sell as hard as I can how fun "stoichiometry" is....I now run the risk of turning a bunch of other kids into THAT kid pretty quickly.
Learn a simple and very inexpensive way to build and use an "absorption spectrometer" using a smartphone. This is a great way to implement Beer's Law experiments in your classroom!
Flinn Scientific has a great elearning video series. Many of the videos have master teachers demonstrating some great labs and techniques that they do in the classroom.
In my IB Chemistry class, my seniors were finishing up independent investigations for their Internal Assessment a few weeks ago when something cool happened. One of my students was using silver nitrate and potassium chromate for a titration. This is notable to the story here because the endpoint is marked by the formation of silver chromate as a precipitate, with a deep reddish color. I overhead the student showing his reaction to another student, with both of them commenting on the cool colors involved.
This year in the midwest United States, winter has been a fickle friend. I haven’t seen the same amount of snow or ice as in recent years, but I still made sure I was prepared for it at our home. I went to my local big box hardware store in December and contemplated buying rock salt (NaCl), and NaCl/calcium chloride mixture, or just calcium chloride. Growing up my dad had switched entirely to calcium chloride because it was less damaging to the brick pavers leading to our porch and backyard. In fact, calcium chloride is generally much safer toward plants and soil than NaCl. Even though calcium chloride is much more expensive than rock salt (it was about twice the cost for 10 pounds more), that what’s I chose. Why?
I just completed covering "ionic and covalent" bonding with my studenets. I wanted to bridge the gap to intermolecular forces. I found a great lab called "Sticky Water" from Target Inquiry - Grand Valley State.(link is external) Before I continue, I have to provide "full disclosure". I spent three years with the Target Inquiry Program at Miami University Ohio (Project TIMU(link is external)). There is a lab called "Sticky Water" that was written by a teacher in the Grand Valley State program. First, the activity focuses on just water, then ethane, then ethanol.