Argument Driven Inquiry and Heat of Solutions

ADI - Enthalpy of Solution

What are we doing to help kids achieve?

I have blogged about (ADI) previously. It has been a popular topic on ChemEd X lately. During my limited experience, I have found the process to be a bit drawn out but extremely helpful and beneficial. The time spent has been well worth it.

A perfect storm of events occurred recently. The April issue of the Journal of Chemical Education (JCE) (Volume 95, Issue 4) has several articles about the dissolving process, concepts of heat, and bond breaking and forming.1,2 My students and I just finished covering heats of reactions and Hess's law and we were starting solution chemistry. Reading those JCE articles got me thinking. The other part to the storm that was helpful was that I found an "Enthalpy of Solution" lab on the NSTA website.3 It is included on a page that offers extra resources related to the Argument-Driven Inquiry in Chemistry: Lab Investigations for Grades 9–12 book that I have discussed before. The part that caught my eye was the particulate drawings for students. One of the drawings illustrated the idea of energy required to break bonds and energy released when ions are hydrated.

I decided to try the lab with my students. I left it up to them to develop an experiment to try to match experimental data with the properties of heat of hydration and dissociation. They had to decide if they should use grams or moles. Many were surprised that there was a change in temperature when substances dissolved. My students' past experience of heats of reactions, specific heat of metals and energy diagrams were helpful aides. I altered the experiment slightly. I made some simple and inexpensive calorimeters. They were simply styrofoam blocks with holes drilled in them to hold large test tubes. Students used about 10 to 15 mL of water each time. One substance was taken off the list. Students had to predict this from their experiment. Perhaps this is similar to the was discussing? Maybe it was not the "authentic assessment" as defined by Grant Wiggins in Ben's blog..but it did have some of the characteristics. Students experienced a high degree of success in their predictions after they developed the experiment and interpreted their data. I did not have to give them the answer. I will say this now and have said this before, I am starting to become a fan of Argument Driven Inquiry. Although I did not interview students....I am sure they preferred a lab over a pen and paper test...especially after a week of state testing. Do you have a unique and interesting lab that has suddenly peaked your interest? Why not share on ChemEd X? We would love to hear from you.

1Timothy N. Abell and Stacey Lowery Bretz, , Journal of Chemical Education2018 95(4), 504-511. (accessed 4/23/18)

2Kinsey Bain and Marcy H. Towns, , Journal of Chemical Education 2018 95 (4), 512-520. (accessed 4/23/18)

3NSTA Press Extras, . is highlighted in this blog. (accessed 4/23/18)