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.
Just as our lives and various circumstances have a story, so do our laboratory experiences. Often the labs we do lack context but we expect students to buy in to the experiment without knowing the what, where, or why of the story. What makes this lab worth doing? What question(s) are we trying to answer? Why was someone exploring this in the first place?
Each spring my Local Section of The American Chemical Society (ACS) hosts a rigorous two part exam as part of the selection process for the The International Chemistry Olympiad (IChO) IChO is an annual international competition for the world’s top chemistry students. Each year, nations from all over the world will send teams of four to compete for top honors.
A perfect storm starts to form. We are on the concept of moles and I have some students who are struggling mathematically. It is a rough time of year to get kids excited. Many students are struggling with ACT and SAT prep and as a teacher, I am tired of test...test...test. Also, I had about two dozen 2 liter bottle "pre forms" that I needed to find something to do with.
I hate to sound like a broken record but I used two activities from Grand Valley State Target Inquiry Program (link is external) that worked amazingly well and had a great "flow". Chad Bridle wrote two inquiry activities that dovetail together. The first is "Changes You Can Believe In". Students are presented first with nine cards that are particulate drawings of changes that occur in matter.
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.
Last winter I watched a webinar put on by ACS and AACT called "NGSS in the Chemistry Classroom." As a result of watching that webinar, I took an activity that had NGSS Science & Engineering Practices (SEP) integrated into it and tried it out in class. In this activity, students are required to develop their own procedures and data tables.
There is a hydrate lab which is done by many teachers. Typically, students first use a known hydrate and are provided the formula. As an example, they might use CuSO4. 5H2O. On paper, they would work through the percent by mass of water in copper (II) sulfate pentahydrate. They then would be given a mass of the copper (II) sulfate pentahydrate, calculate how much water they should lose and then they would heat it and compare the data with the calculated value. Next, they are given an unknown hydrate. They are also given the molar mass of the unknown salt of the hydrate and they have to calculate the molar ratio of salt to water based on their data. Here is one possible way to “tweak” this lab.
We, as teachers, can see that life is sometimes like this and we care enough about our students that we want to try to prepare them for careers and problems that we can’t even imagine….because we believe that good education can empower people to go further and reach higher than they could ever dream….and maybe the journey we will start together begins with a simple question in which the answer may not seem immediately obvious...and that is O.K….